CVE-2026-26275
Vulnérabilité élevée dans httpsig-rs (junkurihara)
Description
httpsig-hyper is a hyper extension for http message signatures. An issue was discovered in `httpsig-hyper` prior to version 0.0.23 where Digest header verification could incorrectly succeed due to misuse of Rust's `matches!` macro. Specifically, the comparison `if matches!(digest, _expected_digest)` treated `_expected_digest` as a pattern binding rather than a value comparison, resulting in unconditional success of the match expression. As a consequence, digest verification could incorrectly return success even when the computed digest did not match the expected value. Applications relying on Digest verification as part of HTTP message signature validation may therefore fail to detect message body modification. The severity depends on how the library is integrated and whether additional signature validation layers are enforced. This issue has been fixed in `httpsig-hyper` 0.0.23. The fix replaces the incorrect `matches!` usage with proper value comparison and additionally introduces constant-time comparison for digest verification as defense-in-depth. Regression tests have also been added to prevent reintroduction of this issue. Users are strongly advised to upgrade to the patched version. There is no reliable workaround without upgrading. Users who cannot immediately upgrade should avoid relying solely on Digest verification for message integrity and ensure that full HTTP message signature verification is enforced at the application layer.
Gravité et risque d'exploitation
CVE-2026-26275 obtient un score CVSS de 7.5/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.28 %, ce qui la place devant 18.8 % des CVE référencées.
Que faire ?
- Vérifiez si httpsig-rs (versions < 0.0.23) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
Références
- https://github.com/junkurihara/httpsig-rs/security/advisories/GHSA-7v42-g35v-xrch
- https://github.com/junkurihara/httpsig-rs/pull/14
- https://github.com/junkurihara/httpsig-rs/pull/15
- https://github.com/junkurihara/httpsig-rs/commit/5533f596c650377e02f4aa9e3eb8dba591b87370
- https://github.com/junkurihara/httpsig-rs/commit/65cbd19b395180a4bba09a89746c4b14ccb8d297
