OS Command InjectionWeakness · CWE-78

CVE-2026-56004

CRITICAL · 10.0 CVSS v3.1 Published 2026-07-02
Patch available
A vendor patch is available. No clean upgrade release — apply the published patch.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click Patch available 8 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A shellcode injection in the mercurial handler of the obs tar_scm source service before version 0.12.4 could be used by attackers able to provide a _service file to execute code as the source service or the local user checking out the malicious services

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A shellcode injection vulnerability exists in the mercurial handler of the obs tar_scm source service, allowing attackers who can provide a malicious _service file to execute arbitrary code either as the source service user or as the local user checking out the affected services.

MitigationUpgrade obs tar_scm source service to version 0.12.4 or later to remediate this vulnerability. Additionally, restrict and validate _service file sources to prevent untrusted parties from injecting malicious content.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify if obs tar_scm source service is installed
    Check for the presence of the obs tar_scm package or source service components on the system. Look for package manager entries or source service directories.
    Affected if obs tar_scm is installed and in use as a source service
  2. Determine the installed version of obs tar_scm
    Query the package manager for the installed version of obs tar_scm (e.g., rpm -q, dpkg -l, or gem list for ruby packages) and compare it to version 0.12.4
    Affected if The installed version is earlier than 0.12.4 or the version cannot be determined (unknown) and obs tar_scm is present
  3. Check for mercurial handler usage in _service files
    Inspect any _service files in build service projects or source repositories. Look for <service name="tar_scm"> entries that specify <param name="scm">mercurial</param> or similar mercurial-related parameters.
    Affected if _service files exist that configure tar_scm with mercurial as the SCM source
  4. Verify source validation for _service files
    Review the build service configuration to determine whether _service files are sourced from untrusted or external repositories without validation.
    Affected if _service files can be provided by untrusted parties or are not validated before use

A user is affected if obs tar_scm with mercurial handler is installed with a version earlier than 0.12.4 and processes _service files from sources that are not trusted or validated.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Patch available Apply the vendor patch
Vendor patch github.com →
Interim mitigation

Upgrade obs tar_scm source service to version 0.12.4 or later to remediate this vulnerability. Additionally, restrict and validate _service file sources to prevent untrusted parties from injecting malicious content.

Recommended fix Moderate confidence

version 0.12.4 or later

  1. 1. Identify the obs-tar_scm source service installation in your environment
  2. 2. Check the current installed version of the tar_scm package
  3. 3. Upgrade the tar_scm package to version 0.12.4 or later
  4. 4. Verify the upgrade was successful by checking the installed version
  5. 5. Review any _service files in use to ensure they were not maliciously modified

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation4.0 h
  • Implementation2.0 h
  • Testing4.0 h
  • Review / QA2.0 h
12.0 hours of engineering $2,120
Get the patch applied

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,392.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-56004 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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