CVE-2026-12478CWE-125

CVE-2026-12478

Medium · published July 14, 2026

CVSS v3.1
4.8
EPSS
0%
Percentile
14.3
In the wild
Unconfirmed
What it is

The fix for CVE-2026-0716 (commit 6ff7ef0, libsoup 3.6.6) placed the integer overflow guard inside the if (masked) block, leaving unmasked server-to-client frames unprotected. A malicious WebSocket server can send a crafted unmasked frame with a payload length near UINT64_MAX to trigger an OOB read in a libsoup-based client when max_incoming_payload_size is set to 0.

The record
Technical detail
CVSS v3.1
4.8 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L
CVSS v4.0
Not supplied
EPSS
0.00241 · 14.3th percentile
Weakness
CWE-125 · Out-of-bounds Read
Published
2026-07-14T14:16Z
References (3)
https://access.redhat.com/security/cve/CVE-2026-12478 · [email protected]https://bugzilla.redhat.com/show_bug.cgi?id=2489655 · [email protected]https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/518 · [email protected]
EPSS history
Timeline
  • 14 JUL 09:26Z
    Libsoup: incomplete fix for cve-2026-0716: out-of-bounds read in libsoup websocket frame processing (unmasked path)
    cvelistv5