CVE-2026-20310
CRITICAL 9.1As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Catalyst SD-WAN 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-2026-20310 are related to improper link resolution before file access issues that are grouped under the Common Weakness Enumeration (CWE) CWE-59.
Severe if exploited (CVSS 9.1), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.4%chance of exploitation in 30 days · 33rd percentile
Impact if exploited
9.1CVSS 3.1 · CRITICAL
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ⚠Privileges: Requires an admin / high-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-20310/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-20310/poc.json
Weakness (CWE)
- CWE-59: Improper Link Resolution Before File Access ('Link Following')
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
All CVSS metrics
- CRITICAL 9.1 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H - CRITICAL 9.1 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H