CVE-2026-12478

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.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-12478
https://bugzilla.redhat.com/show_bug.cgi?id=2489655
https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/518

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-14 10:16

Updated : 2026-09-16 09:17

NVD link : CVE-2026-12478

Mitre link : CVE-2026-12478

CVE.ORG link : CVE-2026-12478

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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