CVE-2026-20779
HIGH 7.1 PoC AVAILABLEGitea versions from 1.5.0 before 1.26.3 have a TOTP single-use enforcement defect that allows a valid TOTP code to be accepted more than once across web two-factor authentication flows and the Basic Auth X-Gitea-OTP path.
EXPLOIT AVAILABLE
Public exploit or PoC code exists. Modeled probability is still low, but the barrier to attack is reduced — watch closely.
Exploitation likelihood
0.5%chance of exploitation in 30 days · 38th percentile
○ In CISA KEV
● Public exploit / PoC
Impact if exploited
7.1CVSS 3.1 · HIGH
- ConfidentialityHigh
- IntegrityLow
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ⚠User interaction: A user must take an action (click / open a file)
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- reference https://github.com/go-gitea/gitea/security/advisories/GHSA-gx3v-q759-g323
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-20779/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-2026-20779/poc.json
Weakness (CWE)
- CWE-294: Authentication Bypass by Capture-replay
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
All CVSS metrics
- HIGH 7.1 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N - HIGH 7.1 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N