CVE-2026-31685 (GCVE-0-2026-31685)

Vulnerability from cvelistv5 – Published: 2026-04-25 08:47 – Updated: 2026-04-27 14:05
VLAI?
Title
netfilter: ip6t_eui64: reject invalid MAC header for all packets
Summary
In the Linux kernel, the following vulnerability has been resolved: netfilter: ip6t_eui64: reject invalid MAC header for all packets `eui64_mt6()` derives a modified EUI-64 from the Ethernet source address and compares it with the low 64 bits of the IPv6 source address. The existing guard only rejects an invalid MAC header when `par->fragoff != 0`. For packets with `par->fragoff == 0`, `eui64_mt6()` can still reach `eth_hdr(skb)` even when the MAC header is not valid. Fix this by removing the `par->fragoff != 0` condition so that packets with an invalid MAC header are rejected before accessing `eth_hdr(skb)`.
Severity ?
9.4 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 288138418bef956f8b295751a4536c60f0e89f4a (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 9eda5478746ef7dc0e4e537b5a5e4b0ca1027091 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 807d6ee15804df6f01a35c910f09612e858739a6 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 309ae3e9a51a69699ca94eac5fac5688fa562d55 (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < fdce0b3590f724540795b874b4c8850c90e6b0a8 (git)
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    Linux Linux Affected: 2.6.12
Unaffected: 0 , < 2.6.12 (semver)
Unaffected: 6.6.136 , ≤ 6.6.* (semver)
Unaffected: 6.12.83 , ≤ 6.12.* (semver)
Unaffected: 6.18.24 , ≤ 6.18.* (semver)
Unaffected: 6.19.14 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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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.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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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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