The Pulsar broker serves two schema commands on its binary protocol: GetSchema, which returns the schema registered for a topic, and GetOrCreateSchema, which registers a new schema version for an existing topic. The broker handled both commands after checking only that the client connection was authenticated. Unlike the broker's other topic commands, such as those for creating producers and consumers or for looking up topics, these two commands did not check whether the authenticated client was authorized for the target topic. The Pulsar REST API endpoints for schemas were not affected. An authenticated client without any permission on the target topic, namespace or tenant could use these commands to: - read the schema registered for a topic in another namespace or tenant, disclosing the schema definition such as record field names and types. Message payloads are not disclosed. - register a new schema version on an existing topic in another namespace or tenant. The topic's schema compatibility and schema auto-update policies still apply. The issue does not allow message data to be read or modified, but a registered schema version can cause legitimate producers and consumers of that topic to fail with schema incompatibility errors until the schema is corrected by an administrator. The standard Pulsar client performs an authorized topic lookup before it sends these commands, so the missing check could not be observed when testing with the standard client. A client that implements the binary protocol directly is not required to perform that lookup first. This issue is relevant only to deployments that have authentication and authorization enabled. The GetSchema command is affected from Apache Pulsar 2.2.0, and the GetOrCreateSchema command from Apache Pulsar 2.5.0. After the fix, the broker requires the lookup permission on the topic for GetSchema and the produce permission on the topic for GetOrCreateSchema. This impact analysis assumes that Pulsar has been configured with the default authorization provider. For custom authorization providers, the impact could be slightly different. This issue affects Apache Pulsar versions from 2.2.0 before 4.0.14, from 4.1.0 through 4.1.3, and from 4.2.0 before 4.2.5. - 4.0.x version users should upgrade to at least 4.0.14. - 4.1.x and 4.2.x version users should upgrade to at least 4.2.5. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. The currently supported Apache Pulsar release lines are 4.0.x and 5.0.x. The supported versions schedule is available at https://pulsar.apache.org/contribute/release-policy/.

Apache Pulsar's MultiRolesTokenAuthorizationProvider authorizes a client with all roles listed in a claim of its JSON Web Token (JWT). The provider is intended for use with token authentication, which verifies the token before authorization. The provider did not verify the token itself: it parsed the token's claims with the signature removed and trusted that authentication had already checked it. When authentication and authorization are enabled with a non-empty anonymousUserRole setting, some HTTP requests whose credentials fail authentication are not rejected, but are handled as requests of the anonymous user role. For the broker's HTTP endpoints, such as the admin REST API, this fallback applies to requests that do not name an authentication method and requires strictAuthMethod to be false (the default) where that setting is available. For the WebSocket API, failed credentials can also fall back to the anonymous user role; this path does not enforce strictAuthMethod. The authentication data kept for such a request still contained the request's Authorization header. MultiRolesTokenAuthorizationProvider then read the bearer token from that header without verifying its signature and authorized the request with the roles in the token's role claim. As a result, in deployments that use MultiRolesTokenAuthorizationProvider together with a non-empty anonymousUserRole and that permit this fallback, an unauthenticated client can send an HTTP request, for example to the admin REST API or the WebSocket API, with a forged or unsigned token that lists arbitrary roles, and be authorized with those roles. The impact can include super-user access when the token lists a role configured in superUserRoles, allowing the client to read and change tenants, namespaces, topics, permissions and broker configuration. No valid credentials are required. Deployments are not affected if they use the default authorization provider (PulsarAuthorizationProvider) or another authorization provider, or if anonymousUserRole is not set (the default). Requests that authenticate successfully with a valid token are not affected, because the token that MultiRolesTokenAuthorizationProvider reads is the token that authentication verified. Connections that use the Pulsar binary protocol are not affected by this issue, because the broker does not keep client authentication data for connections that it assigns to the anonymous user role. In fixed versions, MultiRolesTokenAuthorizationProvider obtains roles only from tokens that the configured token authentication provider has verified, using its configured keys and validation settings. Broker HTTP requests that are assigned to the anonymous user role are authorized only as that role, and invalid tokens cannot supply additional roles to WebSocket requests. The broker fails to start if MultiRolesTokenAuthorizationProvider is configured with authorization enabled but without a token authentication provider. This issue affects Apache Pulsar versions from 2.8.1 before 4.0.14 and from 4.1.0 before 4.2.5. - 4.0.x version users should upgrade to at least 4.0.14. - 4.1.x and 4.2.x version users should upgrade to at least 4.2.5. Users operating versions prior to those listed above should upgrade to the aforementioned patched versions or newer versions. The currently supported Apache Pulsar release lines are 4.0.x and 5.0.x. The supported versions schedule is available at https://pulsar.apache.org/contribute/release-policy/. Users who cannot upgrade immediately can remove the anonymousUserRole setting from the broker and WebSocket service configurations, or restrict network access to the HTTP endpoints of these services to trusted clients.

A vulnerability in the control channel socket implementation of Open Source Snort 3 could allow an authenticated, local attacker with low privileges to execute arbitrary commands as the Snort 3 process user. This vulnerability is due to a lack of authentication when a local user connects to the Snort control channel socket. An attacker could exploit this vulnerability by connecting to the Snort 3 control channel socket as a local user. A successful exploit could allow the attacker to execute arbitrary commands as well as read and write Snort 3 process memory.

A vulnerability in the IPv4 packet processing functionality of Cisco IOS XR Software that affects Cisco ASR 9000 and 9900 Series Aggregation Services Routers as well as Cisco ASR 9902 and 9903 Compact High-Performance Routers could allow an unauthenticated, remote attacker to cause network processor (NP) errors, resulting in a line card reset or shutdown and a denial of service (DoS) condition.  This vulnerability is due to the incorrect handling of crafted IPv4 packets that are received on an affected line card interface and processed as for-us traffic. The issue can result in an NP reset, causing traffic loss on the affected line card while it recovers. Under repeated reset conditions, the network processor may enter a persistent shutdown state, in which case an explicit line card reload may be required to restore traffic. The vulnerability is within the IPv4 packet-processing path. Transit IPv4 traffic does not trigger this issue and IPv6 traffic cannot trigger it.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76497 are related to issues concerning insecure temporary files that are grouped under the Common Weakness Enumeration (CWE) Base CWE-377.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76496 are related to issues concerning improper link resolutions that are grouped under the Common Weakness Enumeration (CWE) Base CWE-59.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76495 are related to issues concerning incorrect permission assignments that are grouped under the Common Weakness Enumeration (CWE) Variant CWE-732.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76494 are related to issues concerning code injections that are grouped under the Common Weakness Enumeration (CWE) Base CWE-94.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76493 are related to issues concerning uncaught exceptions that are grouped under the Common Weakness Enumeration (CWE) Base CWE-248.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76492 are related to issues concerning null pointers that are grouped under the Common Weakness Enumeration (CWE) Base CWE-476.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76491 are related to issues concerning reachable assertions that are grouped under the Common Weakness Enumeration (CWE) Base CWE-617.

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76490 are related to issues concerning out-of-bounds writes that are grouped under the Common Weakness Enumeration (CWE) Base CWE-787.

Multiple Cisco products are affected by a vulnerability in the memory management implementation of Snort 3 that could allow an unauthenticated, remote attacker to cause the Snort 3 Detection Engine to restart, resulting in an interruption of packet inspection. This vulnerability is due to incomplete error checking when Snort 3 processes files, which could cause unreleased memory. An attacker could exploit this vulnerability by sending a large number of files to be processed. A successful exploit could allow the attacker to cause the Snort 3 Detection Engine to restart unexpectedly, resulting in a DoS condition.

A vulnerability in Cisco Unified Communications Manager (Unified CM) and Cisco Unified Communications Manager Session Management Edition (Unified CM SME) could allow an unauthenticated, remote attacker to conduct access control bypass attacks on an affected device. This vulnerability is due to improper input validation for specific HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to access parts of the network that are beyond the scope of their intended access.

As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams for Cisco Emergency Responder, Cisco Prime Collaboration Deployment, Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unity Connection have conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76481 are related to issues concerning improper handling of exceptional conditions that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-703.

As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams for Cisco Emergency Responder, Cisco Prime Collaboration Deployment, Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unity Connection have conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76479 are related to issues concerning improper limitation of a pathname to a restricted directory that are grouped under the Common Weakness Enumeration (CWE) Base CWE-22.

As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams for Cisco Emergency Responder, Cisco Prime Collaboration Deployment, Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unity Connection have conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76478 are related to improper access control issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-284.

As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams for Cisco Emergency Responder, Cisco Prime Collaboration Deployment, Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unity Connection have conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76477 are related to issues concerning improper neutralization of special elements used in an SQL command that are grouped under the Common Weakness Enumeration (CWE) Base CWE-89.

As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams for Cisco Emergency Responder, Cisco Prime Collaboration Deployment, Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unity Connection have conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76476 are related to issues concerning improper input validation that are grouped under the Common Weakness Enumeration (CWE) Class CWE-20.

As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams for Cisco Emergency Responder, Cisco Prime Collaboration Deployment, Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unity Connection have conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76475 are related to issues concerning improper neutralization of input during web page generation that are grouped under the Common Weakness Enumeration (CWE) Base CWE-79.

As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams for Cisco Emergency Responder, Cisco Prime Collaboration Deployment, Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unity Connection have conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76474 are related to issues concerning improper authentication that are grouped under the Common Weakness Enumeration (CWE) Class CWE-287.

As part of Cisco's ongoing commitment to proactive security and product quality, engineering teams for Cisco Emergency Responder, Cisco Prime Collaboration Deployment, Cisco Unified Communications Manager (Unified CM), Cisco Unified Communications Manager IM & Presence Service (Unified CM IM&P), Cisco Unified Communications Manager Session Management Edition (Unified CM SME), and Cisco Unity Connection have conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-76473 are related to issues concerning improper control of a resource through its lifetime that are grouped under the Common Weakness Enumeration (CWE) Class CWE-74.  

A vulnerability in the database service feature of Cisco Expressway Series could allow an unauthenticated, remote attacker with network access to a Cisco Expressway device to execute arbitrary operating system commands as root. This vulnerability is due to the use of persistent cookies. Additionally, there is insufficient validation of client certificates when the TLS Verify Mode is set to Enabled for clustering, which means that client certificates are not validated. An attacker with possession of the cookies could exploit this vulnerability by connecting to the database service and invoking specific remote procedure call (RPC) commands. A successful exploit could allow the attacker to execute arbitrary commands as root on the underlying operating system of an affected device. Note: Cisco Expressway Series refers to Cisco Expressway Core (Expressway-C) devices and Cisco Expressway Edge (Expressway-E) devices.

A vulnerability in the interprocess communication (IPC) channel of the Secure Firewall Posture module in Cisco Secure Client could allow an authenticated, local attacker to elevate privileges on an affected device. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a series of crafted IPC messages to a local socket. A successful exploit could allow the attacker to perform limited file write operations on the filesystem with SYSTEM or root privileges. Although this vulnerability affects the Secure Firewall Posture module in Cisco Secure Client on Windows, macOS, and Linux operating systems, this vulnerability could be used to obtain full root privileges on macOS and Linux. For that reason Cisco has assigned this security advisory a Security Impact Rating (SIR) of High rather than Medium as the score indicates.

Multiple Cisco products are affected by a vulnerability in the Snort 3 Detection Engine that could allow an unauthenticated, remote attacker to cause the detection engine to unexpectedly restart, resulting in a denial of service (DoS) condition. The vulnerability is due to a flaw in logic handling when General Packet Radio Service (GPRS) Tunneling Protocol (GTP) extension headers are processed within the codec. An attacker could exploit this vulnerability by sending a crafted, fragmented UDP datagram that contains these headers to the Snort 3 Detection Engine of an affected device. A successful exploit could allow the attacker to cause the detection engine to enter an infinite loop, resulting in a DoS condition.