# CVE-2026-91859: MISP access log corruption on request exceptions

Source: https://junglewise.ai/threats/cve-2026-91859-misp-access-log-corruption-on-request-exceptions  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-15. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-91859 · Severity: info · Published 2026-09-15

MISP, an open-source threat intelligence platform, can record incorrect access log data when HTTP requests terminate with an exception. The bug causes the system to log metrics like request duration, database query count, and memory usage twice—once correctly and once incorrectly—with the second corrupted entry overwriting the first. This leads to inaccurate audit trails and performance metrics, potentially masking security issues or creating false incident reports.

Technologies: [Misp](https://junglewise.ai/threats/technologies/misp). Vendors: [Misp](https://junglewise.ai/threats/vendors/misp).

## Quick answers

**Is CVE-2026-91859 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-91859 being exploited in the wild.

**How severe is CVE-2026-91859?** Informational severity, published 15 September 2026.

**Which products and versions are affected?** Misp ≤2.5.45.

**Is there a fix for CVE-2026-91859?** A patch was published on 2026-09-15: Commit 0dae5c0 addresses the double-logging issue Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-91859 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-91859?** Check whether you run Misp 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.

## Technical details

This is a logic flaw in exception handling within MISP's CakeErrorController. When an exception occurs, CakeErrorController extends AppController and re-executes the application startup path, causing the __accessMonitor() hook to call AccessLog::logRequest() twice for a single HTTP request. The second call occurs during error-controller execution and overwrites the database row created by the first pass with incorrect metrics (duration, SQL counts, memory). The bug went undetected because the model instance retained the INSERT ID from the first save, causing the second operation to issue an UPDATE rather than create an obvious duplicate row. A fix was committed in 2026 that prevents the error controller from updating the access-log entry.

## Affected products

- MISP MISP ≤2.5.45

## Timeline

- 2026-09-15: disclosed
- 2026-09-15: patched: Commit 0dae5c0 addresses the double-logging issue

## References

- [https://github.com/MISP/MISP/commit/0dae5c072](https://github.com/MISP/MISP/commit/0dae5c072)

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