Improper Authentication in Linux kernel - CVE-2026-68300

Vulnerability identifier: #VU142011

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-68300

CWE-ID: CWE-287

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote user to bypass authentication.

The vulnerability exists due to improper authentication in sctp_auth_chunk_verify() when processing SCTP chunks with a NULL auth_chunk. A remote user can send a specially crafted SCTP chunk to bypass authentication.

This can occur for new connections or when no AUTH chunk precedes a COOKIE-ECHO chunk.

Linux kernel
Red Hat Enterprise Linux for Real Time
Red Hat Enterprise Linux for Real Time for NFV
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Red Hat CodeReady Linux Builder for x86_64
Red Hat CodeReady Linux Builder for Power, little endian
Red Hat CodeReady Linux Builder for ARM 64
kernel (Red Hat package)
kernel-rt (Red Hat package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel (Red Hat package) - update to 4.18.0-553.162.1.el8_10
kernel-rt (Red Hat package) - update to 4.18.0-553.162.1.rt7.503.el8_10

• https://git.kernel.org/stable/c/18957373920caf5cdaf5cf32e5d1d7a99ca7700a
• https://git.kernel.org/stable/c/28c5fdce9dd955d2baf5e28987819b6d7cfaf646
• https://git.kernel.org/stable/c/83f5031f2a6a49d696eb4cc0898345d12f9c6451
• https://git.kernel.org/stable/c/8e04823c120b376ef7dab14b60ebf6823aa16c14
• https://git.kernel.org/stable/c/ec2e157fc9678a9bc411305a25aec3fd337d7efb

• Improper Authentication in Linux kernel sctp
• Red Hat Enterprise Linux 8 update for kernel-rt
• Red Hat Enterprise Linux 8 update for kernel