CVE-2026-58426: Critical Vulnerability in Gitea Actions Allows Unauthorized Data Access
This text was generated using artificial intelligence (AI).On the widely used, self-hosted Git platform Gitea A critical security vulnerability with a CVSS score of 9.6 (Critically) disclosed. The vulnerability, according to the security advisory GHSA-hg5r-vq93-9fv6 as CVE-2026-58426 This vulnerability affects the Gitea Actions feature. It allows authenticated attackers with low privileges to bypass security boundaries between different projects in order to access sensitive build artifacts and manipulate their upload status. A security update to address the issue is available.
The Facts at a Glance:
- CVE ID: CVE-2026-58426 (Advisory: GHSA-hg5r-vq93-9fv6)
- CVSS Score: 9.6 (Critical)
- Affected component: Gitea instances with Actions enabled
- Effect: Unauthorized read access to build artifacts and write access to the upload status across repository boundaries.
- Solution: Upgrade to Gitea Version 1.26.4 or the latest stable version (Note: Version 1.26.2 contains a known regression; Gitea recommends updating directly to 1.26.4).
Technical Analysis of CVE-2026-58426
The cause of the vulnerability lies in an ambiguity in the cryptographic verification of HMAC signatures used for signed URLs in the Gitea Actions Artifacts V4 API. An attacker who already has low-privileged access to the Gitea instance can send specially crafted requests to the API. Due to the faulty signature verification, the system incorrectly interprets these requests as legitimate.
The CVSS score CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N illustrates the potential threat:
- AV:N (Network): The attack can be carried out remotely over the network.
- AC:L (Low): Carrying out the attack does not require a high degree of complexity.
- PR:L (Low): An attacker only needs an account with low privileges.
- C:H (High Confidentiality) & I:H (High Integrity): The impact on data confidentiality and integrity is significant.
The fix was implemented in pull request #37707, which modifies the structure of the signature payload to ensure unique validation.
Business Risks Posed by Compromised CI/CD Pipelines
This vulnerability poses a significant risk to companies that use a central Gitea instance for multiple development teams or projects. Build artifacts are a key component of CI/CD processes and often contain sensitive information such as:
- Compiled application binaries and libraries
- Configuration files containing login credentials for databases or cloud services
- Private API Keys and Tokens
- Intellectual property in the form of source code or proprietary assets
By taking advantage of CVE-2026-58426 An attacker with access to a non-critical repository can breach logical isolation and gain access to artifacts from highly secure production pipelines. This can lead to the theft of trade secrets, the compromise of production environments, or the manipulation of the software supply chain.
CVE-2026-58426 is not the first critical security vulnerability found in Gitea: As recently as May 2026, CVE-2026-27771 (CVSS 8.2), a vulnerability was patched that allowed unauthenticated attackers to retrieve private container images from an estimated 30,000+ affected deployments worldwide. This spate of critical vulnerabilities underscores the need for systematic vendor risk management. (Source: SecurityWeek, TheHackerNews, May 2026 — https://www.securityweek.com/gitea-vulnerability-exposed-30000-deployments-to-attacks/)
According to security researchers, Germany is among the countries with the highest density of exposed Gitea instances. Organizations subject to NIS-2 or the GDPR should treat compromised build artifacts as a potential data breach and, if necessary, consider filing a report in accordance with GDPR Article 33 within 72 hours. Operators of critical infrastructure are also subject to the reporting requirements under the BSI Act.
Recommended countermeasures
Administrators of Gitea instances should take immediate action to secure their systems.
Immediate action:
- Upgrade to Gitea Version 1.26.4 or the latest stable version. The original security patch was released on May 20, 2026, as version 1.26.2; however, since 1.26.2 contains a known regression, Gitea recommends updating directly to 1.26.4.
Long-Term Strategy:
- Set up continuous vulnerability monitoring for your entire IT infrastructure so you can be notified promptly of new security vulnerabilities.
- Implement a vendor risk management system to systematically assess and monitor the security of third-party products in use.
Visibility and Control with LocateRisk
Self-hosted systems such as Gitea are an important part of the development infrastructure, but without continuous monitoring, they can become an uncontrolled risk. Given the growing number of critical vulnerabilities in widely used open-source platforms, the systematic identification and continuous assessment of such systems is crucial.
The LocateRisk platform supports companies in this regard on two levels:
- External Attack Surface Management (EASM): Our solution continuously identifies all publicly accessible systems in your organization, including self-hosted Gitea instances, forgotten subdomains, and unmanaged cloud assets. This gives you visibility into your actual attack surface and allows you to quickly determine whether and where you are affected by vulnerabilities such as CVE-2026-58426—even if systems are not centrally inventoried.
- Continuous Vendor Risk Management (C-VRM): The security of your software supply chain depends on the security of your vendors. The recurring vulnerabilities in Gitea highlight why a one-time assessment is not enough. LocateRisk continuously assesses the security level of your service providers and software vendors and proactively notifies you of new risks.
As a German provider offering hosting in ISO 27001-certified data centers in Germany, LocateRisk helps companies comply with GDPR requirements and reduces the risk of data access by U.S. authorities.
Sources and further information
Do you know your external attack surface?
Continuous monitoring of your external IT systems is the foundation of a resilient security strategy. LocateRisk identifies and assesses security risks in your attack surface before they can be exploited.
Request a free safety check
Frequently asked questions
CVE-2026-58426 refers to a critical vulnerability (CVSS 9.6) in the Gitea Actions Artifacts V4 API. The vulnerability stems from an ambiguity in the HMAC signature verification of signed URLs, which allows a low-privileged attacker to access build artifacts from other projects across repository boundaries and manipulate their upload status. The associated security advisory is listed under the identifier GHSA-hg5r-vq93-9fv6.
This affects Gitea instances with the Actions feature enabled that have not yet been updated to the latest patch. The fix was implemented in version 1.26.2 (released on May 20, 2026, Pull Request #37707). Since version 1.26.2 contains a known regression, Gitea recommends updating directly to Version 1.26.4 or the latest stable version of the 1.26.x branch.
According to security advisory GHSA-hg5r-vq93-9fv6, as of the date of disclosure (July 3, 2026), there are no confirmed reports of active exploitation of the vulnerability in the wild. However, since the attack requires only a low-privileged account and can be carried out over the network without user interaction, the update should still be installed immediately.
English 
Deutsch 
Français