HIGH · 8.2

CVE-2026-43190

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_tcpmss: check remaining length before reading optlen Quoting reporter: In net/netfilter/xt_tcpmss.c (lines 53-68),...

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_tcpmss: check remaining length before reading optlen Quoting reporter: In net/netfilter/xt_tcpmss.c (lines 53-68), the TCP option parser reads op[i+1] directly without validating the remaining option length. If the last byte of the option field is not EOL/NOP (0/1), the code attempts to index op[i+1]. In the case where i + 1 == optlen, this causes an out-of-bounds read, accessing memory past the optlen boundary (either reading beyond the stack buffer _opt or the following payload).

CVSS Score

8.2

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
LinuxLinux Kernel>= 2.6.12.1, < 5.10.252

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-43190?

CVE-2026-43190 is a vulnerability with a CVSS score of 8.2 (HIGH). In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_tcpmss: check remaining length before reading optlen Quoting reporter: In net/netfilter/xt_tcpmss.c (lines 53-68),...

How severe is CVE-2026-43190?

CVE-2026-43190 has been rated HIGH with a CVSS base score of 8.2/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-43190?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.