| Name | CVE-2026-9648 |
| Description | The crypton-x509-validation Haskell library fails to enforce X.509 NameConstraints, allowing TLS clients to accept certificates whose Subject Alternative Names fall outside the issuing CA’s permitted subtrees. This oversight enables an attacker who compromises a name-constrained sub-CA to impersonate domains beyond its intended scope. |
| 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) |
| Debian Bugs | 1139732, 1140406 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| haskell-crypton-x509 (PTS) | trixie | 1.7.7-1 | vulnerable |
| forky, sid | 1.7.7-2 | vulnerable | |
| haskell-crypton-x509-validation (PTS) | trixie | 1.6.12-3 | vulnerable |
| forky, sid | 1.6.14-1 | vulnerable |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| haskell-crypton-x509 | source | (unstable) | (unfixed) | 1140406 | ||
| haskell-crypton-x509-validation | source | (unstable) | (unfixed) | 1139732 |
[trixie] - haskell-crypton-x509 <no-dsa> (Minor issue)
[trixie] - haskell-crypton-x509-validation <no-dsa> (Minor issue)
https://www.kb.cert.org/vuls/id/862559
https://github.com/kazu-yamamoto/crypton-certificate/pull/30
Fixed by: https://github.com/kazu-yamamoto/crypton-certificate/commit/f4b77edf6ead77f4a886da40e41eab20f0180e39 (crypton-x509-validation-1.9.1)
https://haskell.github.io/security-advisories/advisory/HSEC-2026-0008.html