CVE-2026-16615

EUVD-2026-47742

22.07.2026, 17:16

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.

PRNG

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	6.8 MEDIUM	NETWORK	HIGH	NONE	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

Awaiting analysis

This vulnerability is currently awaiting analysis.

Base Score

CVSS 3.x

EPSS Score

Percentile: 15.83%

Debian Releases

Debian Product

Codename

librest

bookworm	vulnerable
forky	vulnerable
sid	vulnerable
trixie	no-dsa

Ubuntu Releases

Ubuntu Product

Codename

librest

bionic	needs-triage
focal	needs-triage
jammy	needs-triage
noble	needs-triage
resolute	needs-triage
xenial	needs-triage

openSUSE / SLES Releases

openSUSE Product

Release

librest-0_7-0

suse enterprise desktop 15 SP7	0.8.1-150600.4.3.1 fixed
suse enterprise sap 15 SP7	0.8.1-150600.4.3.1 fixed
suse enterprise server 15 SP4	0.8.1-150000.3.7.1 fixed
suse enterprise server 15 SP7	0.8.1-150600.4.3.1 fixed
suse enterprise workstation 15 SP7	0.8.1-150600.4.3.1 fixed

librest-1_0-0

suse enterprise desktop 15 SP7	0.9.1-150600.3.3.1 fixed
suse enterprise sap 15 SP7	0.9.1-150600.3.3.1 fixed
suse enterprise server 15 SP7	0.9.1-150600.3.3.1 fixed

librest-devel

suse enterprise desktop 15 SP7	0.9.1-150600.3.3.1 fixed
suse enterprise sap 12 SP5	0.8.0-13.3.1 fixed
suse enterprise sap 15 SP7	0.9.1-150600.3.3.1 fixed
suse enterprise server 12 SP5	0.8.0-13.3.1 fixed
suse enterprise server 15 SP4	0.8.1-150000.3.7.1 fixed
suse enterprise server 15 SP7	0.9.1-150600.3.3.1 fixed

librest0

suse enterprise sap 12 SP5	0.8.0-13.3.1 fixed
suse enterprise server 12 SP3	0.8.0-13.3.1 fixed
suse enterprise server 12 SP5	0.8.0-13.3.1 fixed

librest0-32bit

suse enterprise sap 12 SP5	0.8.0-13.3.1 fixed
suse enterprise server 12 SP3	0.8.0-13.3.1 fixed
suse enterprise server 12 SP5	0.8.0-13.3.1 fixed

librest0_7-devel

suse enterprise desktop 15 SP7	0.8.1-150600.4.3.1 fixed
suse enterprise sap 15 SP7	0.8.1-150600.4.3.1 fixed
suse enterprise server 15 SP7	0.8.1-150600.4.3.1 fixed
suse enterprise workstation 15 SP7	0.8.1-150600.4.3.1 fixed

typelib-1_0-Rest-0_7

suse enterprise desktop 15 SP7	0.8.1-150600.4.3.1 fixed
suse enterprise sap 15 SP7	0.8.1-150600.4.3.1 fixed
suse enterprise server 15 SP4	0.8.1-150000.3.7.1 fixed
suse enterprise server 15 SP7	0.8.1-150600.4.3.1 fixed
suse enterprise workstation 15 SP7	0.8.1-150600.4.3.1 fixed

typelib-1_0-Rest-1_0

suse enterprise desktop 15 SP7	0.9.1-150600.3.3.1 fixed
suse enterprise sap 15 SP7	0.9.1-150600.3.3.1 fixed
suse enterprise server 15 SP7	0.9.1-150600.3.3.1 fixed

Azure Linux Releases

Azure Package

Release

rest

Azure Linux 3.0

0:0.9.0-2.azl3

fixed

Common Weakness Enumeration

CWE-338 - Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG)
The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG's algorithm is not cryptographically strong.

References

https://access.redhat.com/errata/RHSA-2026:47085

https://access.redhat.com/errata/RHSA-2026:62222

https://access.redhat.com/security/cve/CVE-2026-16615

https://bugzilla.redhat.com/show_bug.cgi?id=2504432

https://gitlab.gnome.org/GNOME/librest/-/issues/25