Posts for: #17.12.1

Cisco IOS XE Software on Cisco Catalyst 9500X and 9600X Series Switches Virtual Interface Access Control List Bypass Vulnerability

🚨 SEVERITY: MEDIUM β€” CVSS 5.3 Security Advisory

TL;DR πŸ“Œ

A Medium severity vulnerability has been identified in Cisco IOS XE Software affecting Catalyst 9500X and 9600X Series Switches. An unauthenticated remote attacker could exploit this vulnerability to bypass configured access control lists (ACLs) on affected devices. Cisco has released software updates to address this issue, and there are workarounds available.

What happened πŸ•΅οΈβ€β™‚οΈ

A vulnerability in the access control list (ACL) programming of Cisco IOS XE Software allows an unauthenticated, remote attacker to bypass a configured ACL on affected devices. This occurs when an attacker floods traffic from an unlearned MAC address on a switch virtual interface (SVI) with an egress ACL applied. If the MAC address table is full or flushed, the attacker could successfully bypass the egress ACL.

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Cisco IOS XE Software Secure Boot Bypass Vulnerabilities

🚨 SEVERITY: MEDIUM β€” CVSS 6.7 Security Advisory

TL;DR πŸ“Œ

Multiple vulnerabilities in Cisco IOS XE Software could allow an authenticated local attacker or an unauthenticated attacker with physical access to execute persistent code at boot time, compromising device security. Cisco has released fixed software, and no workarounds are available.

What happened πŸ•΅οΈβ€β™‚οΈ

Cisco has identified multiple vulnerabilities in its IOS XE Software that could allow an attacker to bypass secure boot mechanisms. These vulnerabilities stem from improper validation of software packages, enabling an attacker to place a crafted file on an affected device. This could lead to the execution of persistent code on the operating system, effectively breaking the chain of trust.

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Cisco IOS XE Software Simple Network Management Protocol Denial of Service Vulnerability

🚨 SEVERITY: HIGH β€” CVSS 7.7 Security Advisory

TL;DR πŸ“Œ

A denial of service (DoS) vulnerability has been identified in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS XE Software. An authenticated remote attacker can exploit this vulnerability to cause affected devices to reload unexpectedly. The highest CVSS score for this vulnerability is 7.7, categorized as High severity. Cisco has released software updates to address this issue, but there are no workarounds available.

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Cisco IOS XE Wireless Controller Software Arbitrary File Upload Vulnerability

🚨 SEVERITY: CRITICAL β€” CVSS 10.0 Security Advisory

TL;DR πŸ“Œ

  • A vulnerability in the Out-of-Band Access Point (AP) Image Download, the Clean Air Spectral Recording, and the client debug bundles features of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, remote attacker to upload arbitrary files to an affected system. This vulnerability is due to the presence of a hard-coded JSON Web Token (JWT) on…
  • No fixed release listed yet; apply mitigations and monitor.
  • Workarounds are documented in the advisory.
  • CVEs: CVE-2025-20188.

What happened πŸ•΅οΈβ€β™‚οΈ

A vulnerability in the Out-of-Band Access Point (AP) Image Download, the Clean Air Spectral Recording, and the client debug bundles features of Cisco IOS XE Software for Wireless LAN Controllers (WLCs) could allow an unauthenticated, remote attacker to upload arbitrary files to an affected system.

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