CVE-2026-16615

Librest: weak random number generation in pkce implementation

MEDIUM
6.8
CVSS Score
Published: July 22, 2026 at 04:12 PM UTC
Updated: September 1, 2026 at 06:17 PM UTC
1 product affected across 1 vendorLibrest

Using Red Hat Enterprise Linux 10 by Red Hat?

Get instant alerts when new vulnerabilities affect Red Hat Enterprise Linux 10 - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM6.8
Exploit prediction
EPSS 0.4%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (5)

VDB Entryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/security/cve/CVE-2026-16615
Issue Trackingx_refsource_REDHAT
Source: cverecord
https://bugzilla.redhat.com/show_bug.cgi?id=2504432
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:47085
Vendor Advisoryx_refsource_REDHAT
Source: cverecord
https://access.redhat.com/errata/RHSA-2026:62222

SSVC — Action Prioritization

SSVCNo known exploitNot automatableTotal impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.8MEDIUMredhat
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusAWAITING ANALYSIS
CWE
CWE-338

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card