Instituto Nacional de ciberseguridad. Sección Incibe
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CVE-2026-43190

Severity CVSS v4.0:
Pending analysis
Type:
CWE-125 Out-of-bounds Read
Publication date:
06/05/2026
Last modified:
11/05/2026

Description

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

Impact

Vector 3.x
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 8.20 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): None
Availability (A): High

Base Score 3.x
8.20
Severity 3.x
HIGH

Vulnerable products and versions

CPE From Up to
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 2.6.12.1 (including) 5.10.252 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 5.11 (including) 5.15.202 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 5.16 (including) 6.1.165 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 6.2 (including) 6.6.128 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 6.7 (including) 6.12.75 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 6.13 (including) 6.18.16 (excluding)
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* 6.19 (including) 6.19.6 (excluding)
cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:2.6.12:rc6:*:*:*:*:*:*

To consult the complete list of CPE names with products and versions, see this page


References to Advisories, Solutions, and Tools