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TI-2026-18297 Aliases CVE-2026-22779GHSA-6pw3-h7xf-x4gp

BlackSheep ClientSession is vulnerable to CRLF injection

Priority LOW 34CWE-113Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
None · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub.

Summary

BlackSheep is an asynchronous web framework to build event based web applications with Python. Prior to 2.4.6, the HTTP Client implementation in BlackSheep is vulnerable to CRLF injection. Missing headers validation makes it possible for an attacker to modify the HTTP requests (e.g. insert a new header) or even create a new HTTP request. Exploitation requires developers to pass unsanitized user input directly into headers.The server part is not affected because BlackSheep delegates to an underlying ASGI server handling of response headers. This vulnerability is fixed in 2.4.6.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00368 30th percentileScored 2026-11-07
Fix Fixed BlackSheep (Neoteroi): 2.4.6blacksheep (PyPI): 2.4.6

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
NeoteroiBlackSheepbefore 2.4.62.4.6Patch availableCNA
—blacksheep (PyPI)before 2.4.62.4.6Patch availableGHSA-6pw3-h7xf-x4gp
  • BlackSheep VendorNeoteroi Affected before 2.4.6 Fixed in 2.4.6 Patch available CNA
  • blacksheep (PyPI) Vendor— Affected before 2.4.6 Fixed in 2.4.6 Patch available GHSA-6pw3-h7xf-x4gp

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:neoteroi:blacksheep:*:*:*:*:*:python:*:*before 2.4.6VulnerableNeoteroi
  • cpe:2.3:a:neoteroi:blacksheep:*:*:*:*:*:python:*:* Versions before 2.4.6 Vulnerable ·Neoteroi

Remediation

  • Fix · CNA BlackSheep (Neoteroi) Fixed in 2.4.6
  • Fix · GHSA-6pw3-h7xf-x4gp blacksheep (PyPI) Fixed in 2.4.6 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-22779
  2. 2026-10-03 Alias added: GHSA-6pw3-h7xf-x4gp

References

Patch 1

Advisory 2

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences