CVE-2026-16615

MediumCVSS 6.8

Published: 22/07/2026(UTC)Updated: 01/09/2026(UTC)Translated: 25/07/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.25%

17th percentile - higher than 17% of all known CVEs

Summary

In librest, the PKCE implementation uses the cryptographically insecure GRand function from GLib, allowing an attacker to reverse-engineer the PRNG seed and bypass PKCE protections.

Risk Assessment

An attacker could impersonate the OAuth client and steal access tokens, potentially leading to unauthorized access to protected resources.

Recommendation

Update librest to a version using a cryptographically secure random number generator and regenerate verification codes.

Other vulnerabilities in librest

CVE-2015-2675High
The OAuth implementation in librest before version 0.7.93 incorrectly truncates the pointer returned by the rest_proxy_call_get_url function, allowing remote attackers to cause application crashes by running the EnsureCredentials method from the org.gnome.OnlineAccounts.Account interface on an object representing a Flickr account.

Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS