PyCrypto does not properly reseed PRNG before allowing access

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2013-1445: 1.75% estimated exploitation activity in the next 30 days; percentile 77.82 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

The Crypto.Random.atfork function in PyCrypto before 2.6.1 does not properly reseed the pseudo-random number generator (PRNG) before allowing a child process to access it, which makes it easier for context-dependent attackers to obtain sensitive information by leveraging a race condition in which a child process is created and accesses the PRNG within the same rate-limit period as another process.

Published by the source

17 May 2022, 04:59 UTC

Last modified by the source

21 Oct 2024, 20:52 UTC

Source last checked

26 Oct 2026, 13:22 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-x377-f64p-hf5j

2. Revision 2 · amended · 25 Oct 2026

   Reviewed OSV alias/range/CVSS4 correction; package source scopes and original publication preserved. No customer finding resolved.

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-x377-f64p-hf5j

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# Patch Next advisory brief: CVE-2013-1445

Advisory: PyCrypto does not properly reseed PRNG before allowing access
IDs: CVE-2013-1445, GHSA-x377-f64p-hf5j
Record: https://patchnext.com/advisories/cve-2013-1445 (revision 3, source checked 26 Oct 2026, 13:22 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: pycrypto 2.6.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI pycrypto: affected < 2.6.1; fixed in 2.6.1

## Suggested inspection (read-only)
- `python -m pip show pycrypto`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on pycrypto.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-x377-f64p-hf5j (OSV record GHSA-x377-f64p-hf5j lists affected ranges: PyPI pycrypto >=0 <2.6.1 (fixed))
- Verified: https://github.com/advisories/GHSA-x377-f64p-hf5j (GitHub-reviewed advisory GHSA-x377-f64p-hf5j lists affected ranges: PyPI pycrypto >=0 <2.6.1)

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