CVE-2026-58053 | Gitea act_runner with the Docker backend (through act 0.262.… | CVSS 9.9 CRITICAL

Description

Gitea act_runner with the Docker backend (through act 0.262.0) passes a workflow's container.options string to the Docker job container's HostConfig and, when configured with privileged: false, forces only the Privileged flag off while merging options such as --pid=host, --cap-add, and --security-opt unchanged. A user who can run a workflow on a Docker-backed runner can create a job container with host namespaces and broad capabilities and escape to the host as root despite privileged mode being disabled.

Metadata

CVE ID: CVE-2026-58053
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-06-28 00:55 UTC
Published: 2026-06-28 01:32 UTC
Last updated: 2026-06-28 01:32 UTC
Primary CWE: CWE-269
Improper Privilege Management
Vendor / Product: Gitea / act_runner
Sources: cve.org · NVD

Severity & Metrics

9.9 CRITICAL CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Affected products (1)

Vendor	Product	Platform	Versions
Gitea	act_runner	—	0 ≤ 0.262.0

Weakness (CWE)

CWE	Source	Description
CWE-269	cna	Improper Privilege Management

CVSS scores (2)

Score	Severity	Version	Source	Vector
9.9	CRITICAL	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
9.4	CRITICAL	4.0	cna	CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

References (2)

Proof of Concept https://github.com/bikini/exploitarium/tree/main/gitea-act-runner-container-options-poc
VulnCheck Advisory: Gitea act_runner - Container Hardening Bypass via Workflow Container Options https://www.vulncheck.com/advisories/gitea-act-runner-container-hardening-bypass-via-workflow-container-options