CVE-2026-23456 (GCVE-0-2026-23456)

Vulnerability from cvelistv5 – Published: 2026-04-03 15:15 – Updated: 2026-04-18 08:59
VLAI?
Title
netfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack_h323: fix OOB read in decode_int() CONS case In decode_int(), the CONS case calls get_bits(bs, 2) to read a length value, then calls get_uint(bs, len) without checking that len bytes remain in the buffer. The existing boundary check only validates the 2 bits for get_bits(), not the subsequent 1-4 bytes that get_uint() reads. This allows a malformed H.323/RAS packet to cause a 1-4 byte slab-out-of-bounds read. Add a boundary check for len bytes after get_bits() and before get_uint().
Severity ?
No CVSS data available.
Assigner
Impacted products
Vendor Product Version
Linux Linux Affected: 5e35941d990123f155b02d5663e51a24f816b6f3 , < a2cd54b9348e485d338b3c132338a4410c99afaf (git)
Affected: 5e35941d990123f155b02d5663e51a24f816b6f3 , < c95dc674ebf01ecfb40388b6facfc89b81fed3b7 (git)
Affected: 5e35941d990123f155b02d5663e51a24f816b6f3 , < 41b417ff73a24b2c68134992cc44c88db27f482d (git)
Affected: 5e35941d990123f155b02d5663e51a24f816b6f3 , < 52235bf88159a1ef16434ab49e47e99c8a09ab20 (git)
Affected: 5e35941d990123f155b02d5663e51a24f816b6f3 , < 774a434f8c9c8602a976b2536f65d0172a07f4d2 (git)
Affected: 5e35941d990123f155b02d5663e51a24f816b6f3 , < 6bce72daeccca9aa1746e92d6c3d4784e71f2ebb (git)
Affected: 5e35941d990123f155b02d5663e51a24f816b6f3 , < fb6c3596823ec5dd09c2123340330d7448f51a59 (git)
Affected: 5e35941d990123f155b02d5663e51a24f816b6f3 , < 1e3a3593162c96e8a8de48b1e14f60c3b57fca8a (git)
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    Linux Linux Affected: 2.6.17
Unaffected: 0 , < 2.6.17 (semver)
Unaffected: 5.10.253 , ≤ 5.10.* (semver)
Unaffected: 5.15.203 , ≤ 5.15.* (semver)
Unaffected: 6.1.167 , ≤ 6.1.* (semver)
Unaffected: 6.6.130 , ≤ 6.6.* (semver)
Unaffected: 6.12.78 , ≤ 6.12.* (semver)
Unaffected: 6.18.20 , ≤ 6.18.* (semver)
Unaffected: 6.19.10 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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Show details on NVD website

{
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        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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    "dateReserved": "2026-01-13T15:37:46.020Z",
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    "state": "PUBLISHED"
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  }
}


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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.
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  • 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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