Gitea up to 1.27.1 Markup Context os command injection

Summaryinfo

A vulnerability was found in Gitea up to 1.27.1. It has been classified as critical. The impacted element is an unknown function of the component Markup Context. The manipulation of the argument Context leads to os command injection. This vulnerability is documented as CVE-2026-73539. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Gitea up to 1.27.1. It has been rated as critical. This issue affects an unknown code block of the component Markup Context. The manipulation of the argument Context with an unknown input leads to a os command injection vulnerability. Using CWE to declare the problem leads to CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Gitea substitutes a URL derived from the markup Context field into external renderer command templates without escaping the reference path before shell-style argument splitting. A crafted Context can inject additional renderer arguments, including options that load executable filter files. On deployments using a susceptible external renderer such as pandoc, a user who can place a filter file at an accessible path can cause it to execute as the Gitea service account; the public repository markup endpoint itself can be reachable without authentication.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-73539 since 08/13/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/14/2026). MITRE ATT&CK project uses the attack technique T1202 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

• Gitea

Version

• 1.27.0
• 1.27.1

License

• open-source

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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