Buffer Overflow Affecting pyopenssl package, versions [22.0.0,26.0.0)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-PYTHON-PYOPENSSL-15674459
- published17 Mar 2026
- disclosed16 Mar 2026
- creditjustlife4x4
Introduced: 16 Mar 2026
NewCVE-2026-27459 (opens in a new tab)How to fix?
Upgrade pyopenssl to version 26.0.0 or higher.
Overview
Affected versions of this package are vulnerable to Buffer Overflow via the set_cookie_generate_callback function. An attacker can cause a buffer overflow by providing a callback that returns a cookie value greater than 256 bytes.
Note:
This is only exploitable if the application explicitly uses the set_cookie_generate_callback method on an OpenSSL Context object.