GHSA-cr4g-f395-h25h CVE-2026-20706 GO-2026-5334
Gitea: Token scope bypass on web archive download endpoint
- Severity
- 0.0 / 10
- Critical · CVSS 4.0
- Exploit chance (EPSS)
- 0.59%
- Chance of exploitation in the next 30 days. Higher than 48.18% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-863 Incorrect Authorization
- Fix
1.26.2- Upgrade code.gitea.io/gitea to this version or later
Description
Summary
PR #37698 added checkDownloadTokenScope to /raw/, /media/, and attachment download web endpoints. The /archive/* endpoint (repo.Download in routers/web/repo/repo.go:372) was not included in the fix. This endpoint accepts OAuth2 tokens via webAuth.AllowOAuth2 (registered at routers/web/web.go:1649-1652) but does not call checkDownloadTokenScope or CheckRepoScopedToken.
A personal access token with any non-repository scope (e.g., read:issue or read:misc) can download full repository archives (zip/tar.gz) of private repositories the token owner has access to.
Impact
Scope escalation: tokens scoped to non-repository categories can access full repository content through the archive download endpoint. Higher impact than endpoints fixed in #37698 because /archive/* serves the entire repository.
Steps to Reproduce
- Create a personal access token with ONLY read:misc scope
- Access: GET /{owner}/{private-repo}/archive/main.tar.gz
- Archive is served (200 OK) instead of being rejected (403 Forbidden)
Compare with fixed endpoints:
- GET /{owner}/{private-repo}/raw/branch/main/README.md correctly returns 403
Root Cause
Download function in routers/web/repo/repo.go:372 does not call checkDownloadTokenScope. The outer group middleware reqUnitCodeReader checks repository permission but not token scope.
The API equivalent (/api/v1/repos/{owner}/{repo}/archive/*) IS properly scoped via tokenRequiresScopes(AccessTokenScopeCategoryRepository). The git HTTP endpoints are scoped via CheckRepoScopedToken in httpBase.
Suggested Fix
Add checkDownloadTokenScope(ctx) to Download and InitiateDownload in routers/web/repo/repo.go. The function already exists in routers/web/repo/download.go (same package).
Discovery Method
Variant analysis of PR #37698 — reviewed all web routes with webAuth.AllowOAuth2 middleware.
Affected versions
Go
| Package | Vulnerable | Fixed in |
|---|---|---|
| code.gitea.io/gitea | < 1.26.2 |
1.26.2 |
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 → 1.26.2
- go
go get code.gitea.io/gitea@v1.26.2 && go mod tidy
Severity breakdown
CVSS 4.0 0.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
- Attack vector
- Network
- Attack complexity
- Low
- Attack requirements
- None
- Privileges required
- Low
- User interaction
- None
- Confidentiality (vulnerable system)
- Low
- Integrity (vulnerable system)
- None
- Availability (vulnerable system)
- None
- Confidentiality (subsequent systems)
- None
- Integrity (subsequent systems)
- None
- Availability (subsequent systems)
- None
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-863: Incorrect Authorization
The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.
How to prevent it
- Architecture and Design: Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
- Architecture and Design: Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor [REF-7].
- Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
- Architecture and Design: For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page. One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.
- System Configuration, Installation: Use the access control capabilities of your operating system and server environment and define your access control lists accordingly. Use a "default deny" policy when defining these ACLs.
References
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| 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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