RHSA-2026:98453 - Security Advisory

Topic

An update for libsoup is now available for Red Hat Enterprise Linux 9.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

The libsoup packages provide an HTTP client and server library for GNOME.

Security Fix(es):

• SoupWebsocketExtensionDeflate: libsoup: libsoup: WebSocket permessage-deflate Unbounded Decompression Remote Denial of Service (CVE-2026-15709)
• libsoup: SoupWebsocketConnection: libsoup: WebSocket remote denial of service via oversized control frame protocol violation (CVE-2026-15711)
• libsoup: libsoup: Heap buffer overflow from WebSocket Pong signal type confusion (CVE-2026-102556)
• libsoup: libsoup: Heap buffer overflow during WebSocket message reassembly (CVE-2026-102557)
• libsoup: libsoup: Heap buffer overflow during WebSocket receive-buffer growth (CVE-2026-102558)
• libsoup: libsoup: Heap buffer overflow during WebSocket client-frame masking (CVE-2026-102559)
• libsoup: libsoup: Heap buffer overflow during outgoing permessage-deflate buffer growth (CVE-2026-102560)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 9 x86_64
• Red Hat Enterprise Linux for IBM z Systems 9 s390x
• Red Hat Enterprise Linux for Power, little endian 9 ppc64le
• Red Hat Enterprise Linux for ARM 64 9 aarch64

Fixes

• BZ - 2499922 - CVE-2026-15709 SoupWebsocketExtensionDeflate: libsoup: libsoup: WebSocket permessage-deflate Unbounded Decompression Remote Denial of Service
• BZ - 2499924 - CVE-2026-15711 libsoup: SoupWebsocketConnection: libsoup: WebSocket remote denial of service via oversized control frame protocol violation
• BZ - 2543229 - CVE-2026-102556 libsoup: libsoup: Heap buffer overflow from WebSocket Pong signal type confusion
• BZ - 2543231 - CVE-2026-102557 libsoup: libsoup: Heap buffer overflow during WebSocket message reassembly
• BZ - 2543274 - CVE-2026-102558 libsoup: libsoup: Heap buffer overflow during WebSocket receive-buffer growth
• BZ - 2543285 - CVE-2026-102559 libsoup: libsoup: Heap buffer overflow during WebSocket client-frame masking
• BZ - 2543296 - CVE-2026-102560 libsoup: libsoup: Heap buffer overflow during outgoing permessage-deflate buffer growth

CVEs

• CVE-2026-15709
• CVE-2026-15711
• CVE-2026-102556
• CVE-2026-102557
• CVE-2026-102558
• CVE-2026-102559
• CVE-2026-102560

References

• https://access.redhat.com/security/updates/classification/#important