| Name | CVE-2026-26962 |
| Description | Rack is a modular Ruby web server interface. From version 3.2.0 to before version 3.2.6, Rack::Multipart::Parser unfolds folded multipart part headers incorrectly. When a multipart header contains an obs-fold sequence, Rack preserves the embedded CRLF in parsed parameter values such as filename or name instead of removing the folded line break during unfolding. As a result, applications that later reuse those parsed values in HTTP response headers may be vulnerable to downstream header injection or response splitting. This issue has been patched in version 3.2.6. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| ruby-rack (PTS) | bullseye | 2.1.4-3+deb11u2 | fixed |
| bullseye (security) | 2.1.4-3+deb11u6 | fixed | |
| bookworm | 2.2.22-0+deb12u1 | fixed | |
| bookworm (security) | 2.2.22-0+deb12u2 | fixed | |
| trixie (security), trixie | 3.1.20-0+deb13u1 | vulnerable | |
| forky, sid | 3.2.6-3 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| ruby-rack | source | experimental | 3.2.6-1 | |||
| ruby-rack | source | bullseye | (not affected) | |||
| ruby-rack | source | bookworm | (not affected) | |||
| ruby-rack | source | (unstable) | 3.2.6-2 |
[bookworm] - ruby-rack <not-affected> (Vulnerable code introduced later)
[bullseye] - ruby-rack <not-affected> (Vulnerable code introduced later)
https://github.com/rack/rack/security/advisories/GHSA-rx22-g9mx-qrhv
Fixed by: https://github.com/rack/rack/commit/d50c4d3dab62fa80b2a276271d0d4fb338cfa7df (v3.2.6)
Fixed by: https://github.com/rack/rack/commit/ae320b46617e9131c34ad77ea15f1c3b036c43e6 (v3.1.22)