Heap Corruption Vulnerability in Libsoup's WebSocket Implementation
CVE-2026-102556

8.6HIGH

Key Information:

Vendor

Red Hat
Status
Red Hat Enterprise Linux 10
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
Red Hat Enterprise Linux 8.4 Extended Update Support Long-life Add-on
Vendor
CVE Published:
29 September 2026

What is CVE-2026-102556?

A vulnerability in libsoup allows for heap corruption due to improper handling of incoming WebSocket Pong frames. Specifically, the SoupWebsocketConnection incorrectly emits the ::pong signal with a GByteArray pointer, despite the signal's declaration to pass a GBytes type. This mismatch can lead to crashes or unpredictable behavior in applications that rely on the documented GBytes API when they encounter a specially crafted Pong frame.

Affected Version(s)

Red Hat Enterprise Linux 10 0:3.6.5-3.el10_2.20

Red Hat Enterprise Linux 8 0:2.62.3-19.el8_10

Red Hat Enterprise Linux 8 0:2.62.3-19.el8_10

References

https://access.redhat.com/errata/RHSA-2026:83384
vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:83618
vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:84586
vendor-advisoryx_refsource_REDHAT

CVSS V3.1

Score:
8.6
Severity:
HIGH
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Red Hat would like to thank Hongduo Zhao for reporting this issue.
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