PatchTheCVECVE-2026-22779: BlackSheep is an asynchronous web framework to build event based web applications with Python
CVE-2026-22779 is a medium-severity flaw (CVSS 5.3) affecting blacksheep. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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 a
Why this priority
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.3 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.4% (top 69%) |
| CISA exploited list | No |
| Weakness | CWE-113 |
| Published | 2026-01-14 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-22779?
blacksheep: upgrade to 2.4.6. Exact commands for each OS are on this page.
Is CVE-2026-22779 being exploited?
CVE-2026-22779 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-22779 affect?
CVE-2026-22779 affects blacksheep. Severity is medium (CVSS 5.3). 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
How urgent is CVE-2026-22779?
Priority 31/100. Remotely exploitable, no login, no user action