How to check if you are exposed to CVE-2020-3118
- Find every Cisco IOS XR system you or your clients run, including ones exposed to the internet. Those come first: CISA only lists flaws attackers are already using.
- Compare each version with the fixed versions in the vendor advisory. Where no fix exists yet, apply the vendor’s mitigation or take the system off the internet.
- Run a credentialed vulnerability scan to catch the systems you missed, then check that the next scan no longer reports CVE-2020-3118.
US federal agencies had to fix this by 2022-05-03. Everyone else should treat that deadline as a guide: if it has passed, this is overdue.
Timeline
- · Added to CISA's Known Exploited Vulnerabilities catalog
- · Fix-by date for US federal agencies, passed 1,643 days ago
Weakness type
More exploited Cisco vulnerabilities
CISA lists 102 exploited Cisco vulnerabilities. The closest matches:
- CVE-2022-20821Cisco IOS XR Open Port VulnerabilityAdded 2022-05-23
- CVE-2010-3035Cisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service VulnerabilityAdded 2022-03-25
- CVE-2009-2055Cisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service VulnerabilityAdded 2022-03-25
- CVE-2020-3569Cisco IOS XR Software DVMRP Memory Exhaustion VulnerabilityAdded 2021-11-03
- CVE-2020-3566Cisco IOS XR Software DVMRP Memory Exhaustion VulnerabilityAdded 2021-11-03
- CVE-2026-76418Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference VulnerabilityAdded 2026-10-29
- CVE-2026-76519Cisco Secure Email Gateway Relative Path Traversal VulnerabilityAdded 2026-10-14
- CVE-2026-76504Cisco Catalyst SD-WAN Manager Hex Encoding VulnerabilityAdded 2026-09-30
Keep going
Sources: CISA Known Exploited Vulnerabilities catalog (version 2026.10.30); EPSS data from FIRST.org; CVSS and descriptions from the NIST National Vulnerability Database. Checked 2026-11-01. This product uses the NVD API but is not endorsed or certified by the NVD.