High

Pyopenssl Incorrect Memory Management

  • Disclosed: 08.10.2018
  • Updated: 11.10.2026 11:20

It was discovered that pyOpenSSL incorrectly handled memory when performing operations on a PKCS #12 store. A remote attacker could possibly use this issue to cause pyOpenSSL to consume resources, resulting in a denial of service.

This attack appear to be exploitable via Depends upon calling application, however it could be as simple as initiating a TLS connection that would cause the calling application to reload certificates from a PKCS #12 store. This vulnerability appears to have been fixed in 17.5.0.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Python (PyPI) pyopenssl < 17.5.0 17.5.0

References

CVSS score 5.9/10
CVSS vector
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE)
CWE-401, CWE-404
Platform
Python (PyPI)
Package
pyopenssl
Disclosed
08.10.2018
Updated
11.10.2026 11:20

Sources and licenses

OSV / GitHub Advisory Database - PYSEC-2018-24 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - GHSA-2rcm-phc9-3945 - CC BY 4.0

Vulnerability history: pyopenssl

All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.

Total entries
5
First → latest
09.2013 03.2026
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • High 4
  • Low 1

Disclosures per year

  1. 2017: 0
  2. 2018: 2
  3. 2019: 0
  4. 2020: 0
  5. 2021: 0
  6. 2022: 0
  7. 2023: 0
  8. 2024: 0
  9. 2025: 0
  10. 2026: 2

earlier: 1

  1. High CVE-2026-27459 >= 22.0.0, < 26.0.0 26.0.0
  2. Pyopenssl Incorrect Memory Management this entry
    High · 5.9 CVE-2018-1000808 < 17.5.0 17.5.0
  3. High · 8.1 CVE-2018-1000807 < 17.5.0 17.5.0

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