Use-after-free in Linux kernel - CVE-2026-98548

Vulnerability identifier: #VU156850

CSH Severity: Medium

CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98548

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service through kernel memory corruption.

The vulnerability exists due to a use-after-free in the Linux kernel SCTP implementation when processing a bundled stale-cookie ERROR chunk and DATA chunk received from a non-primary peer address while an association is in the COOKIE-ECHOED state. A remote attacker can send this crafted packet as an SCTP peer to leave the association referencing a freed transport object, which a subsequent FWD-TSN chunk or delayed SACK timer can cause the kernel to access, potentially resulting in memory corruption and a denial of service.

Linux kernel
Ubuntu
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-igx (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-aws (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux-nvidia-tegra (Ubuntu package) - update to 5.15.0-1070.72
linux-nvidia-tegra-igx (Ubuntu package) - update to 5.15.0-1059.59
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1070.72~20.04.1
linux (Ubuntu package) - update to 7.0.0-42.42
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17

• https://git.kernel.org/stable/c/1cd246b214dc9acf4e2f11d58c035e1e672fe7d2
• https://git.kernel.org/stable/c/4498467a8af06cfa3d71cb04bd7c4170dec8f449
• https://git.kernel.org/stable/c/6df536c5acbc0abd6f119d02e24f4a2ed97707f4
• https://git.kernel.org/stable/c/854c053c71459f8db7ef07db9cfa4eec5f5206f2
• https://git.kernel.org/stable/c/965e21ea16acb394d5e5801998ca9b0adc669665
• https://git.kernel.org/stable/c/c0af3fd150fdc43821df3bb77e5ec74faf4dfc7a
• https://git.kernel.org/stable/c/d68c9287b3ca0d6faadc61fbcb18d1a6b5493321
• https://git.kernel.org/stable/c/ec23855274a73906b02f0d124fefd9cb3c008b1d

• Use-after-free in Linux kernel sctp
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more
• Ubuntu update for linux-nvidia-tegra, linux-nvidia-tegra-5.15, linux-nvidia-tegra-igx
• Ubuntu update for linux, linux-aws, linux-aws-5.15 and more