CVE-2026-532636lowpan: fix off-by-one in multicast context address compression
- 5.5MediumCVSS base score
- 0.12%Exploitation in 30 daysEPSS · top 98% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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.
Timeline
ID reserved
By Linux
- 16 days later
· 16 days later
Published
- 4 months later
· 4 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium5.5 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.12% · top 98% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.
Affected products
- affected 5609c185f24dffca5f6a9c127106869da150be03 – < f24a58c72a45f4c109f3557a760cc4b60b7a6037
- affected 5609c185f24dffca5f6a9c127106869da150be03 – < da8cbb64b47e9066b40af0de170901caf17b768c
- affected 5609c185f24dffca5f6a9c127106869da150be03 – < 4485d79617520d84ba5a14515e2b5136007d6deb
- affected 5609c185f24dffca5f6a9c127106869da150be03 – < 06ce6fc106b16dec9b535950db626261be865e5b
- affected 5609c185f24dffca5f6a9c127106869da150be03 – < dcb1bec1c32ee5c3878354e087cf5dbee2b7c7af
- affected 5609c185f24dffca5f6a9c127106869da150be03 – < c32f30ef5e66adbfa102348e2e8a23776eb007cb
- affected 5609c185f24dffca5f6a9c127106869da150be03 – < da8808463882c3f3c357b072e25053c2121f1419
- affected 5609c185f24dffca5f6a9c127106869da150be03 – < 2a58899d11009bffc7b4b32a571858f381121837
- affected 4.6
- unaffected < 4.6
- unaffected 5.10.259 – ≤ 5.10.*
- unaffected 5.15.210 – ≤ 5.15.*
- unaffected 6.1.176 – ≤ 6.1.*
- unaffected 6.6.143 – ≤ 6.6.*
- unaffected 6.12.94 – ≤ 6.12.*
- unaffected 6.18.36 – ≤ 6.18.*
- unaffected 7.0.13 – ≤ 7.0.*
- unaffected 7.1 – ≤ *
References
References9
- https://git.kernel.org/stable/c/f24a58c72a45f4c109f3557a760cc4b60b7a6037 (opens in a new tab)
- https://git.kernel.org/stable/c/da8cbb64b47e9066b40af0de170901caf17b768c (opens in a new tab)
- https://git.kernel.org/stable/c/4485d79617520d84ba5a14515e2b5136007d6deb (opens in a new tab)
- https://git.kernel.org/stable/c/06ce6fc106b16dec9b535950db626261be865e5b (opens in a new tab)
- https://git.kernel.org/stable/c/dcb1bec1c32ee5c3878354e087cf5dbee2b7c7af (opens in a new tab)
- https://git.kernel.org/stable/c/c32f30ef5e66adbfa102348e2e8a23776eb007cb (opens in a new tab)
- https://git.kernel.org/stable/c/da8808463882c3f3c357b072e25053c2121f1419 (opens in a new tab)
- https://git.kernel.org/stable/c/2a58899d11009bffc7b4b32a571858f381121837 (opens in a new tab)
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-39214 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-53263)Record last updated .