CVE-2026-102559Libsoup: libsoup: heap buffer overflow during websocket client-frame masking
Updated under an hour ago ()
Does this affect you?
It affects Red Hat Enterprise Linux 10 and 1 other product. Add what you run to find out whether that includes you.
EPSS puts the chance of exploitation in the next 30 days at 0.30%, higher than 21% of scored CVEs.
Do this next
Free account, 1 product
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.
- CVSS
- 8.6 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
- Weakness (CWE)
- CWE-125
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- 0.30% (percentile 21)
- Assigned by
- redhat
- NVD analysis
- Modified
- Record last updated
- Oct 19, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
Red Hat Red Hat Enterprise Linux 10 redhat:enterprise_linux | from 0:3.6.5-3.el10_2.20 not affected | CNA record |
gnome libsoup gnome:libsoup | before 3.7.3 | NVD |
redhat enterprise_linux redhat:enterprise_linux | 7.0; 8.0; 9.0; 10.0 | NVD |
References
- https://access.redhat.com/errata/RHSA-2026:83384vendor-advisory, x-refsource-redhat, third-party-advisory
- https://access.redhat.com/errata/RHSA-2026:83618vendor-advisory, x-refsource-redhat, third-party-advisory
- https://access.redhat.com/errata/RHSA-2026:84586vendor-advisory, x-refsource-redhat
- https://access.redhat.com/security/cve/CVE-2026-102559vdb-entry, x-refsource-redhat, mitigation, third-party-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2543285issue-tracking, x-refsource-redhat, patch, third-party-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.