Red Hat flatpak-builder Hooks os command injection

Summaryinfo

A vulnerability has been found in Red Hat flatpak-builder and classified as problematic. Affected is an unknown function of the component Hooks. This manipulation causes os command injection. The identification of this vulnerability is CVE-2026-86320. The attack can only be executed locally. There is no exploit available.

Detailsinfo

A vulnerability was found in Red Hat flatpak-builder (the affected version unknown). It has been declared as problematic. Affected by this vulnerability is an unknown part of the component Hooks. The manipulation with an unknown input leads to a os command injection vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A flaw was found in flatpak-builder where Git hooks are not disabled when applying patch sources with use-git-am: true. An attacker who can provide a malicious source containing a Git post-applypatch hook can cause the hook to execute on the host during the build process, resulting in arbitrary code execution with the privileges of the user running flatpak-builder.

It is possible to read the advisory at access.redhat.com. This vulnerability is known as CVE-2026-86320 since 09/07/2026. The exploitation appears to be easy. Attacking locally is a requirement. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/17/2026). The attack technique deployed by this issue is T1202 according to MITRE ATT&CK.

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

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-81387). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

• Red Hat

Name

• flatpak-builder

License

• open-source

Website

• Vendor: https://www.redhat.com/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion