CVE-2021-41084
8.7 HIGHhttp4s is an open source scala interface for HTTP
Published: 2021-09-21 · Last updated: 2026-06-17
Severity and scoring
- CVSS
- 8.7 HIGH
- Vector
- CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
- CWE
- CWE-74, CWE-918
Affected products
| Vendor | Product |
|---|---|
| typelevel | http4s |
Description
http4s is an open source scala interface for HTTP. In affected versions http4s is vulnerable to response-splitting or request-splitting attacks when untrusted user input is used to create any of the following fields: Header names (`Header.name`å), Header values (`Header.value`), Status reason phrases (`Status.reason`), URI paths (`Uri.Path`), URI authority registered names (`URI.RegName`) (through 0.21). This issue has been resolved in versions 0.21.30, 0.22.5, 0.23.4, and 1.0.0-M27 perform the following. As a matter of practice http4s services and client applications should sanitize any user input in the aforementioned fields before returning a request or response to the backend. The carriage return, newline, and null characters are the most threatening.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-41084
- [Patch]https://github.com/http4s/http4s/commit/d02007db1da4f8f3df2dbf11f1db9ac7afc3f9d8
- [Exploit reference]https://github.com/http4s/http4s/security/advisories/GHSA-5vcm-3xc3-w7x3
- [Vendor advisory]https://httpwg.org/http-core/draft-ietf-httpbis-semantics-latest.html#fields.values
- [Other]https://owasp.org/www-community/attacks/HTTP_Response_Splitting
- [Patch]https://github.com/http4s/http4s/commit/d02007db1da4f8f3df2dbf11f1db9ac7afc3f9d8
- [Exploit reference]https://github.com/http4s/http4s/security/advisories/GHSA-5vcm-3xc3-w7x3
- [Vendor advisory]https://httpwg.org/http-core/draft-ietf-httpbis-semantics-latest.html#fields.values
- [Other]https://owasp.org/www-community/attacks/HTTP_Response_Splitting
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