CVE-2026-43190
HIGH
CVSS 8.2
No EPSS data
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 details
EPSS
This CVE is not currently listed in the EPSS dataset.
Show JSON
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"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: xt_tcpmss: check remaining length before reading optlen\n\nQuoting reporter:\n In net/netfilter/xt_tcpmss.c (lines 53-68), the TCP option parser reads\n op[i+1] directly without validating the remaining option length.\n\n If the last byte of the option field is not EOL/NOP (0/1), the code attempts\n to index op[i+1]. In the case where i + 1 == optlen, this causes an\n out-of-bounds read, accessing memory past the optlen boundary\n (either reading beyond the stack buffer _opt or the\n following payload)."
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