Bug 2506176

Summary: CVE-2026-16615 mingw-rest: weak random number generation in PKCE implementation [fedora-all]
Product: [Fedora] Fedora Reporter: Guilherme de Almeida Suckevicz <gsuckevi>
Component: mingw-restAssignee: Marc-Andre Lureau <marcandre.lureau>
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: high Docs Contact:
Priority: high    
Version: 45CC: eblima, marcandre.lureau
Target Milestone: ---Keywords: Security, SecurityTracking
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Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["32817975-c882-4169-aab7-5176dd066bca"]}
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Blocks: 2504432    

Description Guilherme de Almeida Suckevicz 2026-07-22 16:12:51 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

A flaw was found in librest, affecting all versions. 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.
Comment 1 Aoife Moloney 2026-08-17 15:35:55 UTC 
This bug appears to have been reported against 'rawhide' during the Fedora Linux 45 development cycle.
Changing version to 45.