Linux Kernel up to 7.0.12 6lowpan lowpan_iphc_mcast_ctx_addr_compress s6_addr off-by-one

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k1.88-

Summaryinfo

A vulnerability was found in Linux Kernel up to 7.0.12 and classified as critical. Impacted is the function lowpan_iphc_mcast_ctx_addr_compress of the component 6lowpan. The manipulation of the argument s6_addr results in off-by-one. This vulnerability was named CVE-2026-53263. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 7.0.12. Affected is the function lowpan_iphc_mcast_ctx_addr_compress of the component 6lowpan. The manipulation of the argument s6_addr with an unknown input leads to a off-by-one vulnerability. CWE is classifying the issue as CWE-193. A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value. The impact remains unknown. CVE summarizes:

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.

The advisory is available at git.kernel.org. This vulnerability is traded as CVE-2026-53263 since 06/09/2026. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 06/25/2026).

Upgrading to version 5.10.259, 5.15.210, 6.1.176, 6.6.143, 6.12.94, 6.18.36 or 7.0.13 eliminates this vulnerability. Applying the patch f24a58c72a45f4c109f3557a760cc4b60b7a6037/da8cbb64b47e9066b40af0de170901caf17b768c/4485d79617520d84ba5a14515e2b5136007d6deb/06ce6fc106b16dec9b535950db626261be865e5b/dcb1bec1c32ee5c3878354e087cf5dbee2b7c7af/c32f30ef5e66adbfa102348e2e8a23776eb007cb/da8808463882c3f3c357b072e25053c2121f1419/2a58899d11009bffc7b4b32a571858f381121837 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Off-by-one
CWE: CWE-193 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.259/5.15.210/6.1.176/6.6.143/6.12.94/6.18.36/7.0.13
Patch: f24a58c72a45f4c109f3557a760cc4b60b7a6037/da8cbb64b47e9066b40af0de170901caf17b768c/4485d79617520d84ba5a14515e2b5136007d6deb/06ce6fc106b16dec9b535950db626261be865e5b/dcb1bec1c32ee5c3878354e087cf5dbee2b7c7af/c32f30ef5e66adbfa102348e2e8a23776eb007cb/da8808463882c3f3c357b072e25053c2121f1419/2a58899d11009bffc7b4b32a571858f381121837

Timelineinfo

06/09/2026 CVE reserved
06/25/2026 +16 days Advisory disclosed
06/25/2026 +0 days VulDB entry created
06/25/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-53263 (🔒)
GCVE (CVE): GCVE-0-2026-53263
GCVE (VulDB): GCVE-100-373818

Entryinfo

Created: 06/25/2026 12:30
Changes: 06/25/2026 12:30 (60)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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