Python CPython up to 3.14.x HTTP Client Proxy Tunnel crlf injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.5$0-$5k2.96-

Summaryinfo

A vulnerability described as problematic has been identified in Python CPython up to 3.14.x. This affects an unknown function of the component HTTP Client Proxy Tunnel Handler. Executing a manipulation can lead to crlf injection. The identification of this vulnerability is CVE-2026-1502. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic was found in Python CPython up to 3.14.x. This vulnerability affects an unknown code block of the component HTTP Client Proxy Tunnel Handler. The manipulation with an unknown input leads to a crlf injection vulnerability. The CWE definition for the vulnerability is CWE-93. The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

CR/LF bytes were not rejected by HTTP client proxy tunnel headers or host.

The advisory is available at github.com. This vulnerability was named CVE-2026-1502 since 01/27/2026. The exploitation appears to be easy. The attack can be initiated remotely. Additional levels of successful authentication are needed for exploitation. The technical details are unknown and an exploit is not available.

Upgrading to version 3.15.0 eliminates this vulnerability. Applying the patch 05ed7ce7ae9e17c23a04085b2539fe6d6d3cef69 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-21519). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.7
VulDB Meta Temp Score: 4.5

VulDB Base Score: 4.7
VulDB Temp Score: 4.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Crlf injection
CWE: CWE-93 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: CPython 3.15.0
Patch: 05ed7ce7ae9e17c23a04085b2539fe6d6d3cef69

Timelineinfo

01/27/2026 CVE reserved
04/10/2026 +72 days Advisory disclosed
04/10/2026 +0 days VulDB entry created
04/10/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 146211
Status: Confirmed

CVE: CVE-2026-1502 (🔒)
GCVE (CVE): GCVE-0-2026-1502
GCVE (VulDB): GCVE-100-356914
EUVD: 🔒

Entryinfo

Created: 04/10/2026 20:38
Updated: 04/10/2026 21:55
Changes: 04/10/2026 20:38 (71), 04/10/2026 21:55 (1)
Complete: 🔍
Cache ID: 216:5BE:103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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