Answer in brief
CVE-2026-43186 records a Critical severity (CVSS 9.8) vulnerability in ipv6: ioam: fix heap buffer overflow in __ioam6_fill_trace_data(). The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 <f4d9d4b8fd839719d564651671e24c62c545c23b || >=9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 <fb3c662fafebc5b9d74417ed1de8759f6bb72143 || >=9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 <632d233cf2e64a46865ae2c064ae3c9df7c8864f || >=9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 <0591d6509c2ff13f09ea2998434aba0c0472e978 || >=9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 <e90346a2f1e8917d5760a44a1f61c44e3b36d96b || >=9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 <ea3632aefc04205436868541638e26f4a74d5637 || >=9ee11f0fff205b4b3df9750bff5e94f97c71b6a0 <6db8b56eed62baacaf37486e83378a72635c04cc | f4d9d4b8fd839719d564651671e24c62c545c23b, fb3c662fafebc5b9d74417ed1de8759f6bb72143, 632d233cf2e64a46865ae2c064ae3c9df7c8864f, 0591d6509c2ff13f09ea2998434aba0c0472e978, e90346a2f1e8917d5760a44a1f61c44e3b36d96b, ea3632aefc04205436868541638e26f4a74d5637, 6db8b56eed62baacaf37486e83378a72635c04cc |
| Linux/Linuxgeneric | 5.15 | Not reported |
Published upstream
May 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
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).
Quoted source text, attributed separately from HOL analysis.