CVE-2026-1502: Vulnerability in Python Software Foundation CPython
CR/LF bytes were not rejected by HTTP client proxy tunnel headers or host.
AI Analysis
Technical Summary
This vulnerability in CPython involves the failure to reject carriage return and line feed (CR/LF) characters in HTTP client proxy tunnel headers or host fields. Such improper input validation can lead to injection issues or header injection attacks as categorized by CWE-93. The CVSS 4.0 vector indicates network attack vector, low attack complexity, partial privileges required, user interaction required, and high impact on integrity and availability. No official remediation level or patch is currently available from the Python Software Foundation. The affected versions include CPython up to 3.15.0a1.
Potential Impact
The vulnerability could allow an attacker with partial privileges and user interaction to manipulate HTTP proxy tunnel headers or host fields by injecting CR/LF characters. This may impact the integrity and availability of the affected system. However, no known exploits have been reported in the wild, and the overall severity is rated medium.
Mitigation Recommendations
Patch status is not yet confirmed — check the Python Software Foundation advisory for current remediation guidance. Until an official fix is released, users should exercise caution when handling HTTP proxy tunnel headers and consider applying any available workarounds or mitigations recommended by the vendor.
CVE-2026-1502: Vulnerability in Python Software Foundation CPython
Description
CR/LF bytes were not rejected by HTTP client proxy tunnel headers or host.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in CPython involves the failure to reject carriage return and line feed (CR/LF) characters in HTTP client proxy tunnel headers or host fields. Such improper input validation can lead to injection issues or header injection attacks as categorized by CWE-93. The CVSS 4.0 vector indicates network attack vector, low attack complexity, partial privileges required, user interaction required, and high impact on integrity and availability. No official remediation level or patch is currently available from the Python Software Foundation. The affected versions include CPython up to 3.15.0a1.
Potential Impact
The vulnerability could allow an attacker with partial privileges and user interaction to manipulate HTTP proxy tunnel headers or host fields by injecting CR/LF characters. This may impact the integrity and availability of the affected system. However, no known exploits have been reported in the wild, and the overall severity is rated medium.
Mitigation Recommendations
Patch status is not yet confirmed — check the Python Software Foundation advisory for current remediation guidance. Until an official fix is released, users should exercise caution when handling HTTP proxy tunnel headers and consider applying any available workarounds or mitigations recommended by the vendor.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- PSF
- Date Reserved
- 2026-01-27T19:10:37.711Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 69d93c061cc7ad14dada4d46
Added to database: 4/10/2026, 6:05:58 PM
Last enriched: 5/14/2026, 2:53:26 AM
Last updated: 5/25/2026, 3:43:16 PM
Views: 145
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