CVE-2026-56750: Code.gitea.io/gitea Gitea Remember-Me Token Theft Not Vulnerability

CRITICAL
Advisory Identifier: GHSA-rgv6-xp99-6mgj
CWE-613
Published
Advisory Summary

CVE-2026-56750 is a CRITICAL gitea remember-me token theft not vulnerability (CWE-613: Insufficient Session Expiration) affecting Code.gitea.io/gitea libraries in the Go ecosystem. The issue involves gitea remember-me token theft not invalidating attacker session. Remediation is available by upgrading affected packages to version 1.27.0.

CVE-2026-56750 at a Glance

CVE Identifier CVE-2026-56750
GHSA Identifier GHSA-rgv6-xp99-6mgj
Severity CRITICAL
CVSS v3.1 Base Score N/A
CWE Classification CWE-613: Insufficient Session Expiration
Affected Product Code.gitea.io/gitea
Package Ecosystem Go
Published Date
Last Updated

How to Fix CVE-2026-56750

To remediate this vulnerability, upgrade all affected Code.gitea.io/gitea dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

code.gitea.io/gitea fixed: 1.27.0
Upgrade code.gitea.io/gitea to 1.27.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for code.gitea.io/gitea

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-56750, inspect your project dependencies for Code.gitea.io/gitea:

inspect dependencies for code.gitea.io/gitea

Analyze the terminal output to locate any version of Code.gitea.io/gitea in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.27.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-613: Insufficient Session Expiration, where according to wasc, "insufficient session expiration is when a web site permits an attacker to reuse old session credentials or session ids for authorization.". In Code.gitea.io/gitea, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

The vulnerability is in the Remember-Me (gitea_incredible) token validation logic, specifically when handling a compromised token (hash mismatch). The vulnerable function is this one: https://github.com/go-gitea/gitea/blob/689ace1ce28fd74244b8aa335d9928cdbf6b22f9/services/auth/auth_token.go#L33-L64 ### Affected Endpoint POST `/user/login` (and any endpoint triggering `autoSignIn` via the Remember-Me cookie). ### Description Gitea implements Remember-Me cookies using a split token design (ID:Hash), [citing the Paragonie secure remember-me guide](https://github.com/go-gitea/gitea/blob/689ace1ce28fd74244b8aa335d9928cdbf6b22f9/services/auth/auth_token.go#L21). When a token is used, its Hash is rotated, but the ID remains the same. If an attacker steals a user's Remember-Me token and uses it to authenticate, the attacker is issued a new rotated token (same ID, new Hash). When the legitimate user later attempts to use their original token, Gitea correctly detects a hash mismatch for the given ID. According to the referenced Paragonie specification, this indicates a compromised token, and ALL active remember-me sessions for that user MUST be invalidated. However, Gitea's `CheckAuthToken` function simply returns `ErrAuthTokenInvalidHash`. The calling code (`autoSignIn`) catches this error and deletes the victim's local cookie via `ctx.DeleteSiteCookie`, but fails to delete the compromised token from the database. As a result, the attacker's active session is never invalidated, and the attacker maintains persistent, indefinite access to the victim's account, entirely defeating the purpose of the split-token security design.

CVE-2026-56750 Affected Code.gitea.io/gitea Versions

1 component(s)
Fixed Versions:
1.27.0
Product / Package Ecosystem Affected Versions Fixed Version
code.gitea.io/gitea
Go
< 1.27.0
1.27.0

References

Frequently Asked Questions

What is CVE-2026-56750?
CVE-2026-56750 is a security vulnerability in Code.gitea.io/gitea involving Gitea Remember-Me Token Theft Not Invalidating Attacker Session under CWE-613: Insufficient Session Expiration.
Which Code.gitea.io/gitea versions are affected?
Affected versions include releases prior to 1.27.0 across affected packages: code.gitea.io/gitea.
What version fixes CVE-2026-56750?
Upgrading to 1.27.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is code.gitea.io/gitea affected?
Yes, code.gitea.io/gitea is affected in releases prior to 1.27.0. Upgrade your dependency to 1.27.0 or later.
What CWE is associated with CVE-2026-56750?
CVE-2026-56750 is classified under CWE-613: Insufficient Session Expiration (According to WASC, "Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization.").
How can I check Go dependencies for CVE-2026-56750?
Run the dependency tree command: 'inspect dependencies for code.gitea.io/gitea'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-rgv6-xp99-6mgj",
  "modified" : "2026-07-21T20:20:21Z",
  "published" : "2026-07-21T20:20:21Z",
  "aliases" : [ "CVE-2026-56750" ],
  "summary" : "Gitea Remember-Me Token Theft Not Invalidating Attacker Session",
  "details" : "The vulnerability is in the Remember-Me (gitea_incredible) token validation logic, specifically when handling a compromised token (hash mismatch).\n\nThe vulnerable function is this one:\n\nhttps://github.com/go-gitea/gitea/blob/689ace1ce28fd74244b8aa335d9928cdbf6b22f9/services/auth/auth_token.go#L33-L64\n\n### Affected Endpoint\nPOST `/user/login` (and any endpoint triggering `autoSignIn` via the Remember-Me cookie).\n\n### Description\nGitea implements Remember-Me cookies using a split token design (ID:Hash), [citing the Paragonie secure remember-me guide](https://github.com/go-gitea/gitea/blob/689ace1ce28fd74244b8aa335d9928cdbf6b22f9/services/auth/auth_token.go#L21). When a token is used, its Hash is rotated, but the ID remains the same.\n\nIf an attacker steals a user's Remember-Me token and uses it to authenticate, the attacker is issued a new rotated token (same ID, new Hash). When the legitimate user later attempts to use their original token, Gitea correctly detects a hash mismatch for the given ID.\n\nAccording to the referenced Paragonie specification, this indicates a compromised token, and ALL active remember-me sessions for that user MUST be invalidated. However, Gitea's `CheckAuthToken` function simply returns `ErrAuthTokenInvalidHash`. The calling code (`autoSignIn`) catches this error and deletes the victim's local cookie via `ctx.DeleteSiteCookie`, but fails to delete the compromised token from the database.\n\nAs a result, the attacker's active session is never invalidated, and the attacker maintains persistent, indefinite access to the victim's account, entirely defeating the purpose of the split-token security design.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "code.gitea.io/gitea"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.27.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/go-gitea/gitea/security/advisories/GHSA-rgv6-xp99-6mgj"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/go-gitea/gitea/pull/38406"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/go-gitea/gitea/pull/38426"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/go-gitea/gitea/commit/de4b8277e9cb576f2315fb03b5ab6478b42a1d31"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/go-gitea/gitea/commit/f69e15afe7496cc62e96dab244629c69eb31a7bf"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/go-gitea/gitea"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/go-gitea/gitea/releases/tag/v1.27.0"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-613" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-07-21T20:20:21Z",
    "nvd_published_at" : null
  }
}