# CVE-2023-26143: blamer arbitrary argument injection in blameByFile() API

Source: https://junglewise.ai/threats/cve-2023-26143-blamer-arbitrary-argument-injection-in-blamebyfile-api  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-09-19. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2023-26143 · Severity: low · CVSS 3.1 · Published 2023-09-19

The blamer Node.js library is used for analyzing file blame history from version control systems. Versions before 1.0.4 fail to properly validate file paths and command-line arguments passed to the underlying git binary, allowing attackers to inject arbitrary git command flags that could lead to information disclosure or repository manipulation.

Technologies: [blamer (npm)](https://junglewise.ai/threats/technologies/blamer). Vendors: [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2023-26143 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2023-26143 being exploited in the wild.

**How severe is CVE-2023-26143?** Low severity, with a CVSS score of 3.1, published 19 September 2023.

**Which products and versions are affected?** blamer (npm) SEMVER:introduced=0,fixed=1.0.4.

**Is there a fix for CVE-2023-26143?** Yes. blamer (npm): upgrade to 1.0.4 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2023-26143 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2023-26143?** Check whether you run blamer (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- blamer (npm): upgrade to 1.0.4 or later

  ```sh
  npm install blamer@1.0.4
  ```


## Technical details

The vulnerability is an arbitrary argument injection (CWE-88) flaw in the blameByFile() API. The library does not sanitize user-supplied file paths or use proper argument delimitation (the POSIX double-dash --) when invoking the git binary, allowing attackers to inject malicious git command-line flags. An attacker with the ability to control the file path argument can inject options to alter git's behavior, potentially exposing sensitive information or modifying repository state. The vulnerability affects all versions prior to 1.0.4, which implements proper input validation and uses -- to delimit options from file arguments.

## Affected products

- kucherenko blamer before 1.0.4

## Identifiers

- CVE-2023-26143
- GHSA-6f9p-g466-f8v8

## Timeline

- 2023-09-19: disclosed
- 2023-09-21: patched: fixed in version 1.0.4

## References

- [https://github.com/kucherenko/blamer/commit/0965877f115753371a2570f10a63c455d2b2cde3](https://github.com/kucherenko/blamer/commit/0965877f115753371a2570f10a63c455d2b2cde3)

## Related threats

- [Blamer command injection via argument injection](https://junglewise.ai/threats/cve-2019-10807-blamer-command-injection-via-argument-injection)
- [blamer code injection](https://junglewise.ai/threats/cve-2020-8137-blamer-code-injection)