GHSA-5v69-g2m3-3hq3 CVE-2026-26232 GO-2026-6336

Gitea OAuth2 authorization codes can be reused after expiry

Critical Go

Severity: 9.1 / 10; Critical · CVSS 3.1
Exploit chance (EPSS): 0.50%; Chance of exploitation in the next 30 days. Higher than 42.50% of scored vulnerabilities.
Known exploited: No; Not in CISA's catalog
Weakness: CWE-294 Authentication Bypass by Capture-replay
Fix: 1.25.5; Upgrade code.gitea.io/gitea to this version or later

Description

Gitea versions before 1.25.5 do not consistently enforce OAuth2 authorization code expiry and single-use behavior during token exchange.

Affected versions

Go

Package	Vulnerable	Fixed in
code.gitea.io/gitea	`< 1.25.5`	`1.25.5`

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

code.gitea.io/gitea Go → `1.25.5`

go

go get code.gitea.io/gitea@v1.25.5 && go mod tidy

Severity breakdown

CVSS 3.1 9.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: None

Weakness

CWE-294: Authentication Bypass by Capture-replay

A capture-replay flaw exists when the design of the product makes it possible for a malicious user to sniff network traffic and bypass authentication by replaying it to the server in question to the same effect as the original message (or with minor changes).

How to prevent it

Architecture and Design: Utilize some sequence or time stamping functionality along with a checksum which takes this into account in order to ensure that messages can be parsed only once.
Architecture and Design: Since any attacker who can listen to traffic can see sequence numbers, it is necessary to sign messages with some kind of cryptography to ensure that sequence numbers are not simply doctored along with content.

References

Advisories

Packages

github.com/go-gitea/gitea

Timeline

Jul 3, 2026 Published
Oct 25, 2026 Last updated by the source
Oct 31, 2026 Latest EPSS score

Advisory	Severity	Why it's related
GHSA-rcr6-4jqh-j84m Gitea: Remote Code Execution via diffpatch Git Hook Installation	Critical Known exploited	Also affects code.gitea.io/gitea
GHSA-fq2p-5p22-8g6j Gitea: Public-Only Personal access tokens scope bypass in Organization and Permission Endpoints	Medium	Also affects code.gitea.io/gitea
GHSA-2wm4-vwp6-v7xc Gitea: SSRF via Migration Asset Downloads Bypasses hostmatcher — Reads Internal Files and Cloud Metadata	High	Also affects code.gitea.io/gitea
GHSA-3r5c-2xxx-h872 Gitea: Webhook Authorization Header Returned in Plaintext via API	Low	Also affects code.gitea.io/gitea
GHSA-frpw-3h2q-4jj6 Gitea: Cross-Repo Information Disclosure via Org-Level Actions Run/Job APIs	Medium	Also affects code.gitea.io/gitea
GHSA-q423-49rw-g9mh Gitea: GHSA-8fwc-qjw5-rvgp ClearRepoWatches fix not applied to API EditRepo path — sister code path retains stale watches on public->private	Medium	Also affects code.gitea.io/gitea
GHSA-2fcr-jfvc-vgg2 Gitea: Two SSRF findings	High	Also affects code.gitea.io/gitea
GHSA-fw57-jgch-pgf3 Gitea: ParseAcceptLanguage quadratic-time DoS via Locale middleware on unauthenticated requests	High	Also affects code.gitea.io/gitea

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