Advisories
Cisco PSIRT Releases August 2026 Security Advisories: 13 Critical CVEs Across SD‑WAN, IOS XE, and More
On Aug 5 2026 Cisco’s Product Security Incident Response Team issued a wave of advisories covering 13 CVEs that span SD‑WAN, IOS XE, Integrated Management Controller, and other components. The most severe flaws—rated 9.8‑9.9 on CVSS—include argument‑injection and denial‑of‑service vectors that could cripple network control planes. Cisco has pushed hardening releases for Catalyst SD‑WAN and IOS XE, urging customers to patch or reconfigure to mitigate the risks.
On August 5 2026, Cisco’s PSIRT announced a comprehensive set of security advisories affecting a wide range of products. The release covers 13 CVEs that range from critical to informational, with the majority falling into the critical or high severity buckets.
Critical Vulnerabilities (CVSS 9.8‑9.9)
- Catalyst SD‑WAN Software Hardening Release (August 2026) – CVE‑2026‑20303, CVE‑2026‑20304, CVE‑2026‑20310, CVE‑2026‑20312, CVE‑2026‑20313 (all critical, 9.9)
- IOS XE Software Hardening Release (August 2026) – CVE‑2026‑20267 through CVE‑2026‑20273 (critical, 9.8)
High‑Severity Issues (CVSS 8.6‑8.8)
- Integrated Management Controller (IMC) argument injection – CVE‑2026‑20200 (8.8)
- IMC cross‑site scripting – CVE‑2026‑20198 (8.6)
- IOS/IOS XE Extensible Messaging Client Protocol DoS – CVE‑2026‑20301 (8.6)
- IOS XE Extensible Exchange Protocol DoS – CVE‑2026‑20263 (8.6)
- IOS XE SNMP DoS – CVE‑2026‑20124 (7.7)
Medium‑Severity Vulnerabilities (CVSS 5.0‑6.5)
- RoomOS logging subsystem info disclosure – CVE‑2026‑20289 (5.7)
- Terminal Services Agent firewall rules bypass – CVE‑2026‑20028 (5.0)
- SD‑WAN Manager info disclosure – CVE‑2026‑20294 (6.5)
- IOS XE web‑based management interface DoS – CVE‑2026‑20311 (6.3)
Informational Notice
Additional low‑impact findings (e.g., CVE‑2026‑20198) were classified as informational and do not require immediate action.
Customers are advised to download the August 2026 hardening releases for Catalyst SD‑WAN and IOS XE, apply any available patches, and review configuration best practices to mitigate the identified risks. Cisco’s PSIRT recommends monitoring for any further updates or mitigations.
Related vulnerabilities
Cisco IOS XE Hardening Release Addresses 7 Critical CVEs – August 2026
Cisco’s IOS XE team rolled out a hardening update in August 2026 that patches seven critical vulnerabilities discovered during internal testing. No workarounds exist; customers should apply the latest firmware to mitigate the risks. The CVEs span multiple CWE categories and carry a Critical impact rating.
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Cisco PSIRT Unveils Batch of Critical & Medium Vulnerabilities – Immediate Patch Required
On Aug. 19 2026, Cisco’s PSIRT released a suite of advisories covering 12 CVEs across Crosswork, Secure Workload, BroadWorks, Unified Intelligence Center, RoomOS, Industrial Ethernet 1000 Series, and Contact Center products. Four critical (CVSS 10.0) affect Crosswork and Secure Workload hardening releases, while a high‑severity XML‑External‑Entity flaw hits BroadWorks. Medium‑rated issues include SQL injection, stack overflow, XSS, DoS, and server‑side request forgery. Cisco urges customers to deploy the fixed builds immediately and notes updates to its vulnerability disclosure process.
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Cisco Catalyst SD‑WAN Hardening Update: Critical Vulnerabilities Resolved (CVE‑2026‑20303‑20313)
Cisco’s SD‑WAN software team released a hardening patch in August 2026 after an internal audit uncovered several critical weaknesses. Five CVEs—CVE‑2026‑20303, ‑20304, ‑20310, ‑20312, ‑20313—were addressed through a single update per CWE class. No workarounds exist, so all Catalyst SD‑WAN customers should apply the new releases immediately to close the gaps.
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Cisco PSIRT to Release Security Hardening Advisories for BroadWorks, ISE, Nexus Dashboard, Secure Firewall, and ThousandEyes on Sep 16, 2026
Cisco’s Product Security Incident Response Team (PSIRT) will publish a set of security hardening advisories on September 16, 2026, covering vulnerabilities in BroadWorks CommPilot Application Software, Identity Services Engine (ISE), Nexus Dashboard, Secure Firewall Adaptive Security Appliance (ASA), Secure Firewall Management Center (FMC), Secure Firewall Threat Defense (FTD), and ThousandEyes Virtual Appliance. The advisories will detail the flaws and provide fixed software releases. Cisco urges customers to apply the updates promptly and notes the shift to a risk‑based vulnerability disclos
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