CVE-2026-22779: Neoteroi BlackSheep · HTTP Request/Response Splitting
Affects Neoteroi BlackSheepSource CVE Database V5
Not known to be exploited · CVSS 6.3 Medium : upgrade to 2.4.6 when convenient.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 30% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 2.4.6
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 14 Jan 2026
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 26 Oct 2026.
What to do
Upgrade BlackSheep and blacksheep to 2.4.6.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| NeoteroiBlackSheep | Affected
| Fixed in
|
PyPIblacksheeppkg:pypi/blacksheepOther 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
European organizations should immediately upgrade BlackSheep to version 2.4.6 or later to ensure the vulnerability is patched. Developers must audit their codebases to identify any instances where user input is incorporated into HTTP headers without proper sanitization or validation. Implement strict input validation and sanitization routines to neutralize CRLF characters before including user data in headers. Employ security code reviews and automated static analysis tools to detect unsafe header manipulations. Additionally, consider implementing Web Application Firewalls (WAFs) with rules to detect and block HTTP header injection attempts. Monitor application logs for unusual HTTP header patterns indicative of exploitation attempts. Educate developers on secure coding practices related to HTTP header construction. Finally, maintain an inventory of applications using BlackSheep to prioritize patching and risk assessment efforts.
Description
CVE-2026-22779 is a medium severity vulnerability in the BlackSheep Python asynchronous web framework's HTTP Client prior to version 2.4.6. It involves improper neutralization of CRLF sequences in HTTP headers, allowing attackers to perform HTTP request/response splitting by injecting malicious headers or creating new HTTP requests. Exploitation requires developers to pass unsanitized user input directly into HTTP headers, and the server-side component is not affected. The vulnerability does not require authentication or user interaction and has a CVSS score of 6.3. No known exploits are currently reported in the wild. The issue is fixed in version 2.4.