Answer in brief
CVE-2026-53263 records a Medium severity (CVSS 5.5) vulnerability in 6lowpan: fix off-by-one in multicast context address compression. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic), Siemens/SIMATIC S7-1500 TM MFP - GNU/Linux subsystem (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 5.5. 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), Siemens/SIMATIC S7-1500 TM MFP - GNU/Linux subsystem (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=5609c185f24dffca5f6a9c127106869da150be03 <f24a58c72a45f4c109f3557a760cc4b60b7a6037 || >=5609c185f24dffca5f6a9c127106869da150be03 <da8cbb64b47e9066b40af0de170901caf17b768c || >=5609c185f24dffca5f6a9c127106869da150be03 <4485d79617520d84ba5a14515e2b5136007d6deb || >=5609c185f24dffca5f6a9c127106869da150be03 <06ce6fc106b16dec9b535950db626261be865e5b || >=5609c185f24dffca5f6a9c127106869da150be03 <dcb1bec1c32ee5c3878354e087cf5dbee2b7c7af || >=5609c185f24dffca5f6a9c127106869da150be03 <c32f30ef5e66adbfa102348e2e8a23776eb007cb || >=5609c185f24dffca5f6a9c127106869da150be03 <da8808463882c3f3c357b072e25053c2121f1419 || >=5609c185f24dffca5f6a9c127106869da150be03 <2a58899d11009bffc7b4b32a571858f381121837 | f24a58c72a45f4c109f3557a760cc4b60b7a6037, da8cbb64b47e9066b40af0de170901caf17b768c, 4485d79617520d84ba5a14515e2b5136007d6deb, 06ce6fc106b16dec9b535950db626261be865e5b, dcb1bec1c32ee5c3878354e087cf5dbee2b7c7af, c32f30ef5e66adbfa102348e2e8a23776eb007cb, da8808463882c3f3c357b072e25053c2121f1419, 2a58899d11009bffc7b4b32a571858f381121837 |
| Linux/Linuxgeneric | 4.6 | Not reported |
| Siemens/SIMATIC S7-1500 TM MFP - GNU/Linux subsystemgeneric | >=0 <* | * |
Published upstream
Jun 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 15, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 25, 2026
In the Linux kernel, the following vulnerability has been resolved: 6lowpan: fix off-by-one in multicast context address compression The second memcpy in lowpan_iphc_mcast_ctx_addr_compress() uses &data[1] as destination and &ipaddr->s6_addr[11] as source, but both should be offset by one: &data[2] and &ipaddr->s6_addr[12] respectively. This off-by-one has two consequences: 1. data[1] is overwritten with s6_addr[11], corrupting the RIID field in the compressed multicast address 2. data[5] is never written, so uninitialized kernel stack memory is transmitted over the network via lowpan_push_hc_data(), leaking kernel stack contents The correct inline data layout must match what the decompression function lowpan_uncompress_multicast_ctx_daddr() expects: data[0..1] = s6_addr[1..2] (flags/scope + RIID) data[2..5] = s6_addr[12..15] (group ID) Also zero-initialize the data array as a defensive measure against similar bugs in the future.
Quoted source text, attributed separately from HOL analysis.