CVE-2026-43190 (GCVE-0-2026-43190)

Vulnerability from cvelistv5 – Published: 2026-05-06 11:27 – Updated: 2026-05-08 12:41
VLAI?
Title
netfilter: xt_tcpmss: check remaining length before reading optlen
Summary
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).
Severity ?
8.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < f895191dc32c53eaf443b6443fe40945b2f92287 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < cd5beda7e0e32865e214f28034bb92c1cecff885 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < eaedc0bc18be46fe7f58170e967959a932c4f824 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 07a9b32eaae792ff7d0fcac14d8920c937c0a9c3 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 8b300f726640c48c3edfe9c453334dd801f4b74e (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 5e13d0a37666955b6cfddc0f73cb40ed645b8a05 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < f6c412dcfd76b0516d51aa847d8f4c7b70381b09 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 735ee8582da3d239eb0c7a53adca61b79fb228b3 (git)
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    Linux Linux Affected: 2.6.12
Unaffected: 0 , < 2.6.12 (semver)
Unaffected: 5.10.252 , ≤ 5.10.* (semver)
Unaffected: 5.15.202 , ≤ 5.15.* (semver)
Unaffected: 6.1.165 , ≤ 6.1.* (semver)
Unaffected: 6.6.128 , ≤ 6.6.* (semver)
Unaffected: 6.12.75 , ≤ 6.12.* (semver)
Unaffected: 6.18.16 , ≤ 6.18.* (semver)
Unaffected: 6.19.6 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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{
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          "product": "Linux",
          "programFiles": [
            "net/netfilter/xt_tcpmss.c"
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        }
      ],
      "cpeApplicability": [
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        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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    "datePublished": "2026-05-06T11:27:59.798Z",
    "dateReserved": "2026-05-01T14:12:55.992Z",
    "dateUpdated": "2026-05-08T12:41:06.952Z",
    "state": "PUBLISHED"
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  }
}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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