# CVE-2025-40843: Ericsson CodeChecker stack overflow in ldlogger library

Source: https://junglewise.ai/threats/cve-2025-40843-ericsson-codechecker-stack-overflow-in-ldlogger-library  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2025-10-28. Updated: 2026-06-05  
License: CC BY 4.0 with a link back

CVE-2025-40843 · Severity: medium · CVSS 5.9 · Published 2025-10-28

CodeChecker, a tool used for static and dynamic software analysis, contains a flaw in its logging component. An attacker could provide specially crafted input to the 'log' command to cause a system crash or potentially execute unauthorized code. This could allow a local user to disrupt operations or gain unauthorized access to the system where the tool is running.

Technologies: [Ericsson Codechecker](https://junglewise.ai/threats/technologies/ericsson-codechecker), [codechecker (PyPI)](https://junglewise.ai/threats/technologies/codechecker). Vendors: [Ericsson](https://junglewise.ai/threats/vendors/ericsson), [PyPI](https://junglewise.ai/threats/vendors/pypi).

## Quick answers

**Is CVE-2025-40843 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-40843 being exploited in the wild.

**How severe is CVE-2025-40843?** Medium severity, with a CVSS score of 5.9, published 28 October 2025.

**Which products and versions are affected?** codechecker (PyPI) <= 6.26.1, ECOSYSTEM:introduced=0,fixed=6.26.2.

**Is there a fix for CVE-2025-40843?** Yes. codechecker (PyPI): upgrade to 6.26.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2025-40843 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2025-40843?** Check whether you run Ericsson Codechecker or codechecker (PyPI) 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

- codechecker (PyPI): upgrade to 6.26.2 or later

  ```sh
  pip install "codechecker>=6.26.2"
  ```


## Technical details

A stack-based buffer overflow exists in the internal 'ldlogger' library of CodeChecker due to the unsafe use of the 'strcpy()' function. The vulnerability occurs when the 'CodeChecker log' command processes command-line arguments, as the destination buffer is fixed at 4096 bytes without length validation. A local attacker can exploit this by providing a crafted, overly long path or argument to the '-b' flag, potentially leading to arbitrary code execution or a denial-of-service condition. The issue is addressed in version 6.26.2.

## Affected products

- Ericsson CodeChecker <= 6.26.1

## Identifiers

- CVE-2025-40843
- GHSA-5xf2-f6ch-6p8r
- PYSEC-2025-100

## Timeline

- 2025-09-22: disclosed
- 2025-09-22: advisory
- 2025-09-22: patched: Fixed in version 6.26.2

## References

- [https://api.github.com/users/barnabasdomozi](https://api.github.com/users/barnabasdomozi)
- [https://github.com/barnabasdomozi](https://github.com/barnabasdomozi)
- [https://api.github.com/users/barnabasdomozi/gists%7B/gist_id%7D](https://api.github.com/users/barnabasdomozi/gists%7B/gist_id%7D)
- [https://api.github.com/users/barnabasdomozi/repos](https://api.github.com/users/barnabasdomozi/repos)
- [https://avatars.githubusercontent.com/u/142594183?v=4](https://avatars.githubusercontent.com/u/142594183?v=4)
- [https://api.github.com/users/barnabasdomozi/events%7B/privacy%7D](https://api.github.com/users/barnabasdomozi/events%7B/privacy%7D)

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