5.5

CVE-2026-53263: linux Off-by-one Error

CVSS: 5.5v3.1MediumModified
AliasesUBUNTU-CVE-2026-53263DEBIAN-CVE-2026-53263CGA-24j8-p6rw-jrmh
Published 25-06-2026Last modified 15-10-2026
Open JSON

Vulnerability summary

CVE-2026-53263 is a medium (CVSS 5.5) Off-by-one Error vulnerability in linux. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 1.5% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.12%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 31 · Related 31
MGASA-2026-0312OPENSUSE-SU-2026:21388-1SUSE-SU-2026:22742-1SUSE-SU-2026:22769-1SUSE-SU-2026:22812-1SUSE-SU-2026:22835-1

Timeline

  1. 25-06-2026
    PublishedVulnerability first disclosed.
  2. 15-10-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.12%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

0.00 pp

From 0.11% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.12%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu167 products
  • linuxAll versions (No fix recorded) | < 5.15.0-198.208 | < 6.8.0-146.146 | < 7.0.0-31.31
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1117.124 | < 6.8.0-1066.69 | < 7.0.0-1012.12
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Chainguard6 products
  • linux-azure-6.18< 6.18.38-r0
  • linux-gcp-6.18< 6.18.38-r0
  • linux-gcp-6.18-bootc-boot-installed< 6.18.38-r0
  • linux-qemu-6.18< 6.18.38-r0
  • linux-qemu-6.18-bootc-boot-installed< 6.18.38-r0
Linux2 products
  • linux≥ 5609c185f24dffca5f6a9c127106869da150be03, < f24a58c72a45f4c109f3557a760cc4b60b7a6037 | ≥ 5609c185f24dffca5f6a9c127106869da150be03, < da8cbb64b47e9066b40af0de170901caf17b768c | ≥ 5609c185f24dffca5f6a9c127106869da150be03, < 4485d79617520d84ba5a14515e2b5136007d6deb | ≥ 5609c185f24dffca5f6a9c127106869da150be03, < 06ce6fc106b16dec9b535950db626261be865e5b | ≥ 5609c185f24dffca5f6a9c127106869da150be03, < dcb1bec1c32ee5c3878354e087cf5dbee2b7c7af | ≥ 5609c185f24dffca5f6a9c127106869da150be03, < c32f30ef5e66adbfa102348e2e8a23776eb007cb | ≥ 5609c185f24dffca5f6a9c127106869da150be03, < da8808463882c3f3c357b072e25053c2121f1419 | ≥ 5609c185f24dffca5f6a9c127106869da150be03, < 2a58899d11009bffc7b4b32a571858f381121837 | 4.6
  • linux_kernel≥ 4.6, < 5.10.259 | ≥ 5.11, < 5.15.210 | ≥ 5.16, < 6.1.176 | ≥ 6.2, < 6.6.143 | ≥ 6.7, < 6.12.94 | ≥ 6.13, < 6.18.36 | ≥ 6.19, < 7.0.13 | 7.1:rc1 | 7.1:rc2 | 7.1:rc3 | 7.1:rc4 | 7.1:rc5 | 7.1:rc6
Debian1 product
  • linux< 6.1.176-1 | < 6.12.94-1 | < 7.0.13-1

4 vendors · 176 products

References

37 links
Show all 37 references