Out-of-bounds read in Linux kernel - CVE-2026-80603
Published: August 28, 2026
Vulnerability identifier: #VU146273
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-2026-80603
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause incorrect connection tracking state.
The vulnerability exists due to an out-of-bounds read in the parse_dcc() function in nf_conntrack_irc when parsing DCC command data without a newline present. A remote attacker can send specially crafted IRC DCC command data to cause incorrect connection tracking state.
The stray read may consume an uninitialized or stale byte, which can lead to an incorrect DCC IP address or port being recorded in the conntrack expectation.
Affected software
Linux kernel
How to mitigate CVE-2026-80603
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
External References
- https://git.kernel.org/stable/c/2393f0bd7a467ad475598f3a5b9de27ca36e3037
- https://git.kernel.org/stable/c/2b70f61f569bb29acb380e6f616a1bbdee15668f
- https://git.kernel.org/stable/c/437e0a3854b3a44ec15afa9ab88ec215adf3a2fd
- https://git.kernel.org/stable/c/910c33e4a8c046c3cc1fa5a465a4d41a1bb398f1
- https://git.kernel.org/stable/c/abb8c32b88ea3f46beb68c34fe9a3ac8ed664e7e
- https://git.kernel.org/stable/c/aff589556ed772cb1c0c2d7b4d91ec45c0c39416
- https://git.kernel.org/stable/c/eeef3b81f449560653662df2dde6f6fe247c5365
- https://git.kernel.org/stable/c/ef6400ca25a13fd6dedbe8ef4a1d0979bbbfe88a