Integer Overflow Vulnerability in libsoup Affecting Red Hat Products
CVE-2026-12478

4.8MEDIUM

Key Information:

Vendor

Red Hat
Status
Red Hat Enterprise Linux 10
Vendor
CVE Published:
14 July 2026

What is CVE-2026-12478?

This vulnerability arises due to the improper placement of an integer overflow guard in libsoup, specifically within the conditional block for masked frames. As a result, unmasked server-to-client frames are vulnerable. A malicious WebSocket server could exploit this flaw by sending a specially crafted unmasked frame with a payload length close to UINT64_MAX. If the max_incoming_payload_size parameter is set to 0, it may lead to an out-of-bounds read in the libsoup-based client, potentially compromising user data and application behavior.

References

https://access.redhat.com/security/cve/CVE-2026-12478
vdb-entryx_refsource_REDHAT
https://access.redhat.com/security/cve/cve-2026-0716
technical-descriptionx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2489655
issue-trackingx_refsource_REDHAT

CVSS V3.1

Score:
4.8
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
None
Availability:
Low
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Red Hat would like to thank Adel Bouachraoui and Gerard Capdevila for reporting this issue.
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