Librest: weak random number generation in pkce implementation (GNOME librest)
At a glance
- Source
- NVD
- EPSS
- EPSS 0.43 % · percentile 38 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- redhat
- NVD status
- Awaiting Analysis
Description
A flaw was found in librest. The PKCE implementation for OAuth authorization uses the GRand function from the GLib API, a cryptographically insecure pseudo-random number generator. Because the generated "code verifier" lacks sufficient cryptographic entropy, a malicious actor can reverse-engineer the pseudo-random number generator (PRNG) seed to predict or reconstruct the code verifier string, allowing an attacker to bypass PKCE protections and successfully impersonate the client during the OAuth 2.0 authorization flow.
Weaknesses (CWE)
- CWE-338 — Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
References
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 6.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N | redhat |
| CVSS 3.1 | MEDIUM 6.8 | CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N | NVD · secalert@redhat.com (Secondary) |
European references
- ENISA EUVD · EUVD-2026-47742
- GCVE · GCVE-0-2026-16615
Affected products
| Product | Versions |
|---|---|
| GNOME · librest | |
| Red Hat · Red Hat Enterprise Linux 10 | unaffected 0:0.9.1-11.el10_2.1 < * |
| Red Hat · Red Hat Enterprise Linux 10.0 Extended Update Support | unaffected 0:0.9.1-11.el10_0.1 < * |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |