CVE-2024-0397: Python Software Foundation CPython · Race Condition
Affects Python Software Foundation CPythonSource CVE Database V5
Not known to be exploited · CVSS 7.4 High · fixed in 3.12.3 : patch Python Software Foundation CPython soon.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.8% chance of exploitation in 30 days – higher than 56% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.12.3, 3.11.9, 3.10.14
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 17 Jun 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Upgrade Python Software Foundation CPython to 3.12.3, 3.11.9 or 3.10.14.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
PyPIcpythonpkg:pypi/cpythonOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
1. Upgrade all Python environments to the patched versions: 3.10.14, 3.11.9, 3.12.3, or 3.13.0a5 as soon as possible. 2. Audit applications to identify usage of ssl.SSLContext methods cert_store_stats() and get_ca_certs(), especially in concurrent or multi-threaded contexts. 3. Avoid calling cert_store_stats() and get_ca_certs() concurrently with certificate loading or during TLS handshakes until patched versions are deployed. 4. Implement runtime monitoring for unexpected crashes or memory errors in Python applications handling TLS connections. 5. For critical systems where immediate upgrade is not feasible, consider isolating or limiting network exposure to reduce attack surface. 6. Engage in thorough testing of Python-based TLS services post-upgrade to ensure stability and correct certificate handling. 7. Stay informed on any emerging exploit reports or additional patches from the Python Software Foundation.
Description
A defect was discovered in the Python “ssl” module where there is a memory race condition with the ssl.SSLContext methods “cert_store_stats()” and “get_ca_certs()”. The race condition can be triggered if the methods are called at the same time as certificates are loaded into the SSLContext, such as during the TLS handshake with a certificate directory configured. This issue is fixed in CPython 3.10.14, 3.11.9, 3.12.3, and 3.13.0a5.
References
- github.com/python/cpython/issues/114572 (opens in a new tab)
- github.com/python/cpython/pull/114573 (opens in a new tab)
- mail.python.org/archives/list/security-announce@python.org/thread/BMAK5BCGKYWNJOACVUSLUF6SFGBIM4VP/ (opens in a new tab)
- github.com/python/cpython/commit/01c37f1d0714f5822d34063ca7180b595abf589d (opens in a new tab)
- github.com/python/cpython/commit/29c97287d205bf2f410f4895ebce3f43b5160524 (opens in a new tab)
- github.com/python/cpython/commit/37324b421b72b7bc9934e27aba85d48d4773002e (opens in a new tab)
- github.com/python/cpython/commit/542f3272f56f31ed04e74c40635a913fbc12d286 (opens in a new tab)
- github.com/python/cpython/commit/b228655c227b2ca298a8ffac44d14ce3d22f6faa (opens in a new tab)
- github.com/python/cpython/commit/bce693111bff906ccf9281c22371331aaff766ab (opens in a new tab)
- openwall.com/lists/oss-security/2024/06/17/2 (opens in a new tab)
- security.netapp.com/advisory/ntap-20250411-0006/ (opens in a new tab)
- lists.debian.org/debian-lts-announce/2024/12/msg00000.html (opens in a new tab)