CVE-2026-0864: Python Software Foundation CPython · Injection
Affects Python Software Foundation CPythonSource CVE Database V5
Not known to be exploited · CVSS 4.1 Medium · fixed in 3.15.0b4 : update Python Software Foundation CPython when convenient.
Data as of 5 Nov 2026, 00:01 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 2% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 3.15.0b4, 3.14.7, 3.13.15 +3
CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 23 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 6 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Python Software FoundationCPython | Affected
| Fixed in
|
| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
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| Python Software FoundationCPython | Affected
| Fixed in
|
| Python Software FoundationCPython | Affected
| Fixed in
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Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
If you cannot patch yet, users should avoid writing multi-line configuration values containing carriage return characters (\r) with configparser if those values can be influenced by untrusted sources. Review and sanitize inputs used in configuration files to prevent injection of unexpected keys and values.
Description
When using the "configparser" module to write configuration files containing multi-line text values with carriage return characters (\r) the resulting file could be injected with unexpected keys and values if the attacker controls the written value.
References
- github.com/python/cpython/pull/151559 (opens in a new tab)
- mail.python.org/archives/list/security-announce@python.org/thread/CV4NE6AFCRJL7XQOHX7J5TSDHUWVWGJS/ (opens in a new tab)
- github.com/python/cpython/issues/143927 (opens in a new tab)
- github.com/python/cpython/commit/5858e42c539dac8394636a6e9b30472b8994851f (opens in a new tab)
- github.com/python/cpython/commit/0adb386f6e68eb2e73d32e19f235d012df009528 (opens in a new tab)
- github.com/python/cpython/commit/71f2e02a52d47417a6fd69f456346cd8aa7aca98 (opens in a new tab)
- github.com/python/cpython/commit/aaf850fd333cd89e9aada03d92aaa788a6cb1bb8 (opens in a new tab)
- github.com/python/cpython/commit/db4a157c790479710a1a840d7937c5c815a6f8b6 (opens in a new tab)
- github.com/python/cpython/commit/12dcbd74d3563016a8cb8c47e4898889f34f74dd (opens in a new tab)
- github.com/python/cpython/commit/274de100bbf4345bd0c23ef5b446722e9e636908 (opens in a new tab)