code.gitea.io/gitea

CVE-2026-27783

CVE-2026-27783 is a medium-severity missing authorization vulnerability in code.gitea.io/gitea (go), affecting versions <= 1.26.1. It is fixed in 1.26.2.

Key facts
CVSS score
4.3
Medium
Attack vector
Network
Issuing authority
GitHub Advisory Database
Affected package
code.gitea.io/gitea
Fixed in
1.26.2
Disclosed
2026

Summary

Summary Three Gitea API endpoints, GET /repos/{owner}/{repo}/issuetemplates, GET /repos/{owner}/{repo}/issueconfig and GET /repos/{owner}/{repo}/issueconfig/validate, read files from the repository's Code default branch (.gitea/ISSUETEMPLATE/ and issueconfig.yaml) and return their contents, but are registered without the reqRepoReader(unit.TypeCode) authorization middleware that every sibling Code-tree endpoint in the same route group carries. A user who has access to a private repository through any single repository unit (for example an organization team granted only the Issues unit, with no Code access) can therefore read the issue-template and issue-config files of that repository's Code tree, which their permission set should not expose. Root cause The three endpoints lack the unit guard routers/api/v1/api.go:1433-1437: m.Get("/issuetemplates", context.ReferencesGitRepo(), repo.GetIssueTemplates) m.Get("/issueconfig", context.ReferencesGitRepo(), repo.GetIssueConfig) m.Get("/issueconfig/validate", context.ReferencesGitRepo(), repo.ValidateIssueConfig) m.Get("/languages", reqRepoReader(unit.TypeCode), repo.GetLanguages) m.Get("/licenses", reqRepoReader(unit.TypeCode), repo.GetLicenses) context.ReferencesGitRepo() only opens the git repository, it performs no permission check. Every other endpoint in this group that reads Code-tree content is guarded with reqRepoReader(unit.TypeCode): /languages, /licenses, /contents/, /file-contents, and /{balltype:tarball|zipball|bundle}/ (api.go:1418-1445). The three issue-template endpoints are the only Code-tree readers in the group missing that guard. The enclosing group runs repoAssignment() (api.go:1446), whose access check is satisfied by HasAnyUnitAccessOrPublicAccess, i.e. access to any unit of the repository is sufficient to pass. Without a per-unit reqRepoReader, the handlers run for a caller who has no Code permission. The handlers return Code-tree file contents routers/api/v1/repo/repo.go: func GetIssueTemplates(ctx context.APIContext) { // :1179 ret := issue.ParseTemplatesFromDefaultBranch(ctx.Repo.Repository, ctx.Repo.GitRepo) ... ctx.JSON(http.StatusOK, ret.IssueTemplates) } func GetIssueConfig(ctx context.APIContext) { // :1209 issueConfig, := issue.GetTemplateConfigFromDefaultBranch(ctx.Repo.Repository, ctx.Repo.GitRepo) ctx.JSON(http.StatusOK, issueConfig) } ParseTemplatesFromDefaultBranch / GetTemplateConfigFromDefaultBranch read .gitea/ISSUETEMPLATE/ and issueconfig.yaml from the default (Code) branch and return them in the JSON response. Proof of Concept victim-org/private-repo is a private repository. The attacker is a member of an organization team granted access to that repository through a non-Code unit only (e.g. the Issues unit), a supported Gitea permission configuration. GET /api/v1/repos/victim-org/private-repo/issuetemplates HTTP/1.1 Host: TARGET Authorization: token <attacker token> The response is 200 OK with the parsed contents of the repository's .gitea/ISSUETEMPLATE/* files. The same applies to /issueconfig. Because the caller lacks the Code unit, every other Code-tree endpoint (/contents, /languages, …) correctly returns 404/403 for the same token, only these three return data. Impact A repository collaborator whose granted permissions exclude the Code unit can read the issue-template and issue-config files from the Code default branch of a private repository. The exposure is limited to those specific configuration files (not arbitrary Code-tree content), which is why this is rated low impact. It is nonetheless a unit-level authorization bypass: the endpoints disclose Code-unit content to callers the permission model is meant to exclude. Suggested fix Add the same unit guard the sibling endpoints use, in routers/api/v1/api.go: m.Get("/issuetemplates", reqRepoReader(unit.TypeCode), context.ReferencesGitRepo(), repo.GetIssueTemplates) m.Get("/issueconfig", reqRepoReader(unit.TypeCode), context.ReferencesGitRepo(), repo.GetIssueConfig) m.Get("/issueconfig/validate", reqRepoReader(unit.TypeCode), context.ReferencesGitRepo(), repo.ValidateIssueConfig) (If issue templates are intended to be visible to Issues-unit users for issue creation, reqRepoReader(unit.TypeIssues) is the appropriate guard, but the current absence of any unit guard is the bug.) References CWE-862 Missing Authorization CWE-284 Improper Access Control OWASP A01:2021 Broken Access Control

Impact

What is missing authorization?

The application does not perform an authorization check before performing a sensitive operation. Typical impact: unauthorized access to restricted functionality or data.

Severity and exposure

CVE-2026-27783 has a CVSS score of 4.3 (Medium). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.

A fixed version is available (1.26.2). Upgrading removes the vulnerable code path.

Affected versions

go

  • code.gitea.io/gitea (<= 1.26.1)

Security releases

  • code.gitea.io/gitea → 1.26.2 (go)
Kodem intelligence

Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.

Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter instead of chasing every advisory.

Kodem's runtime-powered SCA identifies whether CVE-2026-27783 is reachable in your applications. Explore open-source security for your team.

See if CVE-2026-27783 is reachable in your applications. Get a demo

Remediation advice

Upgrade code.gitea.io/gitea to 1.26.2 or later to resolve this vulnerability.

Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.

Frequently asked questions about CVE-2026-27783

What is CVE-2026-27783?

CVE-2026-27783 is a medium-severity missing authorization vulnerability in code.gitea.io/gitea (go), affecting versions <= 1.26.1. It is fixed in 1.26.2. The application does not perform an authorization check before performing a sensitive operation.

How severe is CVE-2026-27783?

CVE-2026-27783 has a CVSS score of 4.3 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.

Which versions of code.gitea.io/gitea are affected by CVE-2026-27783?

code.gitea.io/gitea (go) versions <= 1.26.1 is affected.

Is there a fix for CVE-2026-27783?

Yes. CVE-2026-27783 is fixed in 1.26.2. Upgrade to this version or later.

Is CVE-2026-27783 exploitable, and should I be worried?

Whether CVE-2026-27783 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo

What actually determines whether CVE-2026-27783 is exploitable, and how bad it is?

Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.

How do I fix CVE-2026-27783?

Upgrade code.gitea.io/gitea to 1.26.2 or later.

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