CVE-2026-16615 (GCVE-0-2026-16615)

Vulnerability from cvelistv5 – Published: 2026-07-22 16:12 – Updated: 2026-09-01 17:31
VLAI
Title
Librest: weak random number generation in pkce implementation
Summary
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.
Severity
6.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-22 16:43 UTC
CWE
  • CWE-338 - Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1111 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
GNOME librest guessed Create a notification for this product.
Red Hat Red Hat Enterprise Linux 10 Unaffected: 0:0.9.1-11.el10_2.1 , < * (rpm)
    cpe:/o:redhat:enterprise_linux:10.2
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support Unaffected: 0:0.9.1-11.el10_0.1 , < * (rpm)
    cpe:/o:redhat:enterprise_linux_eus:10.0
Create a notification for this product.
Date Public
2026-06-08 00:00
Credits
Red Hat would like to thank Cole Blakley for reporting this issue.
Show details on NVD website
To clipboard 

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    Related by attack behaviour

    Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.