RHSA-2026:83618HighCVSS 8.6

Red Hat Security Advisory: libsoup3 security update

Published
October 15, 2026
Last Modified
October 16, 2026

🔗 CVE IDs covered (6)

CVE-2026-102555 →CVE-2026-102556 →CVE-2026-102557 →CVE-2026-102558 →CVE-2026-102559 →CVE-2026-102560 →

📋 Description

CVE-2026-102555 — libsoup: libsoup: Heap buffer overflow via uninitialized length in data-URI base64 decoding CVE-2026-102556 — libsoup: libsoup: Heap buffer overflow from WebSocket Pong signal type confusion CVE-2026-102557 — libsoup: libsoup: Heap buffer overflow during WebSocket message reassembly CVE-2026-102558 — libsoup: libsoup: Heap buffer overflow during WebSocket receive-buffer growth CVE-2026-102559 — libsoup: libsoup: Heap buffer overflow during WebSocket client-frame masking CVE-2026-102560 — libsoup: libsoup: Heap buffer overflow during outgoing permessage-deflate buffer growth

🎯 Affected products20

  • Red Hat Enterprise Linux AppStream (v. 10)
  • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)
  • libsoup3-0:3.6.5-3.el10_2.20.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-0:3.6.5-3.el10_2.20.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-0:3.6.5-3.el10_2.20.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-0:3.6.5-3.el10_2.20.src as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-0:3.6.5-3.el10_2.20.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-debuginfo-0:3.6.5-3.el10_2.20.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-debuginfo-0:3.6.5-3.el10_2.20.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-debuginfo-0:3.6.5-3.el10_2.20.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-debuginfo-0:3.6.5-3.el10_2.20.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-debugsource-0:3.6.5-3.el10_2.20.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-debugsource-0:3.6.5-3.el10_2.20.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-debugsource-0:3.6.5-3.el10_2.20.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-debugsource-0:3.6.5-3.el10_2.20.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-devel-0:3.6.5-3.el10_2.20.aarch64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-devel-0:3.6.5-3.el10_2.20.ppc64le as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-devel-0:3.6.5-3.el10_2.20.s390x as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-devel-0:3.6.5-3.el10_2.20.x86_64 as a component of Red Hat Enterprise Linux AppStream (v. 10)
  • libsoup3-doc-0:3.6.5-3.el10_2.20.noarch as a component of Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)

✅ Remediation

For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Workaround: To mitigate this do not pass untrusted data URIs to soup_uri_decode_data_uri(). Workaround: To mitigate avoid connecting custom handlers to SoupWebsocketConnection::pong, or avoid WebSocket use with untrusted peers. Workaround: To mitigate this set a conservative max-total-incoming-message-size / incoming payload limits where the API allows, and do not accept WebSocket connections from untrusted peers. Workaround: To mitigate this configure a finite max-incoming-payload-size (do not set it to 0/unlimited) on SoupWebsocketConnection. Restrict WebSocket exposure to trusted peers. Workaround: To mitigate this enforce application-level limits on outgoing WebSocket message sizes. Do not send untrusted bulk data as a single WebSocket message. Workaround: To mitigate this disable the permessage-deflate WebSocket extension if it is not required, and cap outgoing message sizes.

🔗 References (9)