CVE-2026-102559CWE-125

CVE-2026-102559

High · published September 29, 2026

CVSS v3.1
8.6
EPSS
0%
Percentile
33.5
In the wild
Unconfirmed
What it is

A flaw was found in libsoup. When constructing a masked WebSocket client frame for a very large outgoing payload, size values passed to GByteArray allocation APIs could be truncated while the masking routine still used the full length, causing a heap buffer overflow.

The record
Technical detail
CVSS v3.1
8.6 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
CVSS v4.0
Not supplied
EPSS
0.00404 · 33.5th percentile
Weakness
CWE-125 · Out-of-bounds Read
Published
2026-09-29T22:17Z
Affected products (5)
ProductVersionsFixed in
gnome/libsoup< 3.7.33.7.3
redhat/enterprise_linuxall versions—
redhat/enterprise_linuxall versions—
redhat/enterprise_linuxall versions—
redhat/enterprise_linuxall versions—
References (5)
https://access.redhat.com/errata/RHSA-2026:83384 · [email protected]https://access.redhat.com/errata/RHSA-2026:83618 · [email protected]https://access.redhat.com/errata/RHSA-2026:84586 · [email protected]https://access.redhat.com/security/cve/CVE-2026-102559 · [email protected]https://bugzilla.redhat.com/show_bug.cgi?id=2543285 · [email protected]
EPSS history
Timeline
  • 01 OCT 03:44Z
    EPSS moved — → 0%
    epss
  • 29 SEP 17:15Z
    Libsoup: libsoup: heap buffer overflow during websocket client-frame masking
    cvelistv5