{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-43186", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-05-01T14:12:55.991Z", "datePublished": "2026-05-06T11:27:57.053Z", "dateUpdated": "2026-05-06T11:27:57.053Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-05-06T11:27:57.053Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data()\n\nOn the receive path, __ioam6_fill_trace_data() uses trace->nodelen\nto decide how much data to write for each node. It trusts this field\nas-is from the incoming packet, with no consistency check against\ntrace->type (the 24-bit field that tells which data items are\npresent). A crafted packet can set nodelen=0 while setting type bits\n0-21, causing the function to write ~100 bytes past the allocated\nregion (into skb_shared_info), which corrupts adjacent heap memory\nand leads to a kernel panic.\n\nAdd a shared helper ioam6_trace_compute_nodelen() in ioam6.c to\nderive the expected nodelen from the type field, and use it:\n\n - in ioam6_iptunnel.c (send path, existing validation) to replace\n the open-coded computation;\n - in exthdrs.c (receive path, ipv6_hop_ioam) to drop packets whose\n nodelen is inconsistent with the type field, before any data is\n written.\n\nPer RFC 9197, bits 12-21 are each short (4-octet) fields, so they\nare included in IOAM6_MASK_SHORT_FIELDS (changed from 0xff100000 to\n0xff1ffc00)."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/net/ioam6.h", "net/ipv6/exthdrs.c", "net/ipv6/ioam6.c", "net/ipv6/ioam6_iptunnel.c"], "versions": [{"version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0", "lessThan": "f4d9d4b8fd839719d564651671e24c62c545c23b", "status": "affected", "versionType": "git"}, {"version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0", "lessThan": "fb3c662fafebc5b9d74417ed1de8759f6bb72143", "status": "affected", "versionType": "git"}, {"version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0", "lessThan": "632d233cf2e64a46865ae2c064ae3c9df7c8864f", "status": "affected", "versionType": "git"}, {"version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0", "lessThan": "0591d6509c2ff13f09ea2998434aba0c0472e978", "status": "affected", "versionType": "git"}, {"version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0", "lessThan": "e90346a2f1e8917d5760a44a1f61c44e3b36d96b", "status": "affected", "versionType": "git"}, {"version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0", "lessThan": "ea3632aefc04205436868541638e26f4a74d5637", "status": "affected", "versionType": "git"}, {"version": "9ee11f0fff205b4b3df9750bff5e94f97c71b6a0", "lessThan": "6db8b56eed62baacaf37486e83378a72635c04cc", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["include/net/ioam6.h", "net/ipv6/exthdrs.c", "net/ipv6/ioam6.c", "net/ipv6/ioam6_iptunnel.c"], "versions": [{"version": "5.15", "status": "affected"}, {"version": "0", "lessThan": "5.15", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.202", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.165", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.128", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.75", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.16", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.19.6", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.0", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "5.15.202"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.1.165"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.6.128"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.12.75"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.18.16"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "6.19.6"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15", "versionEndExcluding": "7.0"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/f4d9d4b8fd839719d564651671e24c62c545c23b"}, {"url": "https://git.kernel.org/stable/c/fb3c662fafebc5b9d74417ed1de8759f6bb72143"}, {"url": "https://git.kernel.org/stable/c/632d233cf2e64a46865ae2c064ae3c9df7c8864f"}, {"url": "https://git.kernel.org/stable/c/0591d6509c2ff13f09ea2998434aba0c0472e978"}, {"url": "https://git.kernel.org/stable/c/e90346a2f1e8917d5760a44a1f61c44e3b36d96b"}, {"url": "https://git.kernel.org/stable/c/ea3632aefc04205436868541638e26f4a74d5637"}, {"url": "https://git.kernel.org/stable/c/6db8b56eed62baacaf37486e83378a72635c04cc"}], "title": "ipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data()", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data()\n\nOn the receive path, __ioam6_fill_trace_data() uses trace->nodelen\nto decide how much data to write for each node. It trusts this field\nas-is from the incoming packet, with no consistency check against\ntrace->type (the 24-bit field that tells which data items are\npresent). A crafted packet can set nodelen=0 while setting type bits\n0-21, causing the function to write ~100 bytes past the allocated\nregion (into skb_shared_info), which corrupts adjacent heap memory\nand leads to a kernel panic.\n\nAdd a shared helper ioam6_trace_compute_nodelen() in ioam6.c to\nderive the expected nodelen from the type field, and use it:\n\n - in ioam6_iptunnel.c (send path, existing validation) to replace\n the open-coded computation;\n - in exthdrs.c (receive path, ipv6_hop_ioam) to drop packets whose\n nodelen is inconsistent with the type field, before any data is\n written.\n\nPer RFC 9197, bits 12-21 are each short (4-octet) fields, so they\nare included in IOAM6_MASK_SHORT_FIELDS (changed from 0xff100000 to\n0xff1ffc00)."}], "id": "CVE-2026-43186", "lastModified": "2026-05-06T13:07:51.607", "metrics": {}, "published": "2026-05-06T12:16:37.300", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/0591d6509c2ff13f09ea2998434aba0c0472e978"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/632d233cf2e64a46865ae2c064ae3c9df7c8864f"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/6db8b56eed62baacaf37486e83378a72635c04cc"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e90346a2f1e8917d5760a44a1f61c44e3b36d96b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/ea3632aefc04205436868541638e26f4a74d5637"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/f4d9d4b8fd839719d564651671e24c62c545c23b"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/fb3c662fafebc5b9d74417ed1de8759f6bb72143"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Awaiting Analysis"}

{"bugzilla": {"description": "kernel: ipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data()", "id": "2467143", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2467143"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-1284", "details": ["A flaw was found in the Linux kernel's IPv6 In-situ Operations, Administration, and Maintenance (IOAM) functionality. A remote attacker can send a specially crafted packet that manipulates the `nodelen` field while processing trace data. This manipulation leads to a heap buffer overflow, causing approximately 100 bytes to be written past the allocated memory region. This memory corruption can result in a kernel panic, effectively leading to a Denial of Service (DoS) for the affected system."], "name": "CVE-2026-43186", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Under investigation", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-05-06T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-43186\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-43186\nhttps://lore.kernel.org/linux-cve-announce/2026050640-CVE-2026-43186-4c1f@gregkh/T"], "threat_severity": "Important"}