How severe is CVE-2026-22779?

CVE-2026-22779 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2026-22779 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-22779?

CVE-2026-22779 affects Neoteroi Blacksheep. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-22779?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-22779 have an EU (EUVD) identifier?

Yes. CVE-2026-22779 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2451.

When was CVE-2026-22779 published?

CVE-2026-22779 was published on 2026-01-14 and last updated on 2026-06-17.

CVE-2026-22779

CVE-2026-22779 is a medium-severity vulnerability in Neoteroi Blacksheep with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-113.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v4: 6.3
EPSS exploit prediction: 0% (22nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-2451
Weakness: CWE-113
Affected product: Neoteroi Blacksheep
Published: 2026-01-14
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2026-22779?: 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.
How severe is CVE-2026-22779?: CVE-2026-22779 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2026-22779 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-22779?: CVE-2026-22779 affects Neoteroi Blacksheep. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-22779?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-22779 have an EU (EUVD) identifier?: Yes. CVE-2026-22779 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-2451.
When was CVE-2026-22779 published?: CVE-2026-22779 was published on 2026-01-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:neoteroi:blacksheep:*:*:*:*:*:python:*:*

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