Quick answers
- Is CVE-2026-20274 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-20274 being exploited in the wild.
- How severe is CVE-2026-20274?
- Critical severity, with a CVSS score of 9.8, published 2 September 2026.
- Which products and versions are affected?
- Cisco IOS XR Software All releases, including IOS XR7 (LNT).
- Is there a fix for CVE-2026-20274?
- A patch was published on 2026-09-02: Software hardening releases available Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-20274 attacked?
- It is attacked over the network, in an operating system.
- Am I affected by CVE-2026-20274?
- Check whether you run Cisco IOS XR Software at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
CVE-2026-20274 addresses improper resource control issues (CWE-664) within Cisco IOS XR Software, covering multiple vulnerability classes including buffer overflows, out-of-bounds access, use-after-free, and insecure resource initialization. The vulnerabilities are network-accessible with no authentication or user interaction required, allowing remote code execution. The advisory indicates these issues were discovered internally and are not currently being actively exploited in the wild. Cisco has released software hardening updates; no workarounds are available, making patching the only mitigation path.
Affected products
- Cisco IOS XR Software All releases, including IOS XR7 (LNT)
Timeline
- 2026-09-02: disclosed: CVE-2026-20274 and related vulnerabilities disclosed
- 2026-09-02: patched: Software hardening releases available