CVE-2026-43186 (GCVE-0-2026-43186)

Vulnerability from cvelistv5 – Published: 2026-05-06 11:27 – Updated: 2026-05-11 22:19
VLAI?
Title
ipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data()
Summary
In the Linux kernel, the following vulnerability has been resolved: ipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data() On the receive path, __ioam6_fill_trace_data() uses trace->nodelen to decide how much data to write for each node. It trusts this field as-is from the incoming packet, with no consistency check against trace->type (the 24-bit field that tells which data items are present). A crafted packet can set nodelen=0 while setting type bits 0-21, causing the function to write ~100 bytes past the allocated region (into skb_shared_info), which corrupts adjacent heap memory and leads to a kernel panic. Add a shared helper ioam6_trace_compute_nodelen() in ioam6.c to derive the expected nodelen from the type field, and use it: - in ioam6_iptunnel.c (send path, existing validation) to replace the open-coded computation; - in exthdrs.c (receive path, ipv6_hop_ioam) to drop packets whose nodelen is inconsistent with the type field, before any data is written. Per RFC 9197, bits 12-21 are each short (4-octet) fields, so they are included in IOAM6_MASK_SHORT_FIELDS (changed from 0xff100000 to 0xff1ffc00).
Severity ?
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 , < f4d9d4b8fd839719d564651671e24c62c545c23b (git)
Affected: 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 , < fb3c662fafebc5b9d74417ed1de8759f6bb72143 (git)
Affected: 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 , < 632d233cf2e64a46865ae2c064ae3c9df7c8864f (git)
Affected: 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 , < 0591d6509c2ff13f09ea2998434aba0c0472e978 (git)
Affected: 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 , < e90346a2f1e8917d5760a44a1f61c44e3b36d96b (git)
Affected: 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 , < ea3632aefc04205436868541638e26f4a74d5637 (git)
Affected: 9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 , < 6db8b56eed62baacaf37486e83378a72635c04cc (git)
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Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (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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    "dateReserved": "2026-05-01T14:12:55.991Z",
    "dateUpdated": "2026-05-11T22:19:30.665Z",
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  }
}


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Taxonomy of the tags.




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

Author Source Type Date Other

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.



Detection rules are retrieved from Rulezet.