CyberSecBulletin
CVE-2026-12171NVD status: Deferred

auto-changelog: Improper Limitation of a Pathname to a Restricted Directory

CVE-2026-12171 is a high-severity improper limitation of a pathname to a restricted directory vulnerability in auto-changelog from Cookpete, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 2.6.1 as the first without the flaw, so updating auto-changelog to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.22% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update auto-changelog to 2.6.1 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
Cookpeteauto-changelogbefore 2.6.12.6.1

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Scored by CNA.

Scoring systemScoreSeverityScored by
CVSS 4.08.4HighCNA
CVSS 3.17.8HighCNA

Official description

auto-changelog before 2.6.1 merges configuration from inside the target repository (the .auto-changelog file and the auto-changelog key in package.json) into its options, and honors security-sensitive options from that untrusted source. The handlebarsSetup option is passed to require(), so running auto-changelog over attacker-controlled repository content (for example, in a CI workflow that checks out an untrusted pull request head, or locally on a forked or third-party repository) executes attacker-chosen code with the privileges of the invoking user or CI job, including access to workflow secrets, without the repository dependencies ever being installed. The plugins option similarly loads attacker-controlled modules from the repository. Under the same conditions, appendGitLog/appendGitTag allow git argument injection (e.g. --output= to write arbitrary files), output allows writing attacker-influenced content to arbitrary paths, and template causes an outbound request to an attacker-chosen URL. Version 2.6.1 treats in-repository configuration as untrusted and refuses to run when it sets these options, unless the new --unsafe-config flag is passed.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory

The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

How developers prevent this class of flaw

  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
  • Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.

More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities

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