What is RHSA-2026:21656?

RHSA-2026:21656 is a security advisory published by Red Hat Product Security with High severity. Red Hat Security Advisory: OpenShift Container Platform 4.18.43 bug fix and security update

Which CVE IDs does RHSA-2026:21656 cover?

RHSA-2026:21656 covers the following CVE IDs: CVE-2026-27135, CVE-2026-35535, CVE-2026-46300. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of RHSA-2026:21656?

RHSA-2026:21656 has a CVSS v3 base score of 7.8, published by Red Hat Product Security.

RHSA-2026:21656HighCVSS 7.8

Red Hat Security Advisory: OpenShift Container Platform 4.18.43 bug fix and security update

Vendor

Red Hat Product Security

Published

June 3, 2026

Last Modified

June 4, 2026

🔗 CVE IDs covered (3)

CVE-2026-27135 →CVE-2026-35535 →CVE-2026-46300 →

📋 Description

CVE-2026-27135 — nghttp2: nghttp2: Denial of Service via malformed HTTP/2 frames after session termination CVE-2026-35535 — sudo: Sudo: Privilege escalation due to failure in privilege drop calls CVE-2026-46300 — kernel: "Fragnesia" is a variant of Dirty Frag vulnerability in the ESP/XFRM leading to Local Privilege Escalation (LPE) vulnerability in the Linux kernel

🔗 References (6)

selfhttps://access.redhat.com/errata/RHSA-2026:21656
externalhttps://access.redhat.com/security/updates/classification/#important
externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2448754
externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2454714
externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2477015
selfhttps://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_21656.json