Import Source
https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-90642.json
JSON Data
https://api.test.osv.dev/v1/vulns/AZL-90642
Upstream
Published
2026-06-25T09:16:42Z
Modified
2026-08-28T17:45:57Z
Summary
CVE-2026-53249 affecting package kernel for versions less than 6.6.143.1-1
Details

In the Linux kernel, the following vulnerability has been resolved:

ipv4: restrict IPOPT_SSRR and IPOPT_LSRR options

This patch restricts setting Loose Source and Record Route (LSRR) and Strict Source and Record Route (SSRR) IP options to users with CAP_NET_RAW capability.

This prevents unprivileged applications from forcing packets to route through attacker-controlled nodes to leak TCP ISN and possibly other protocol information.

While LSRR and SSRR are commonly filtered in many network environments, they may still be supported and forwarded along some network paths.

RFC 7126 (Recommendations on Filtering of IPv4 Packets Containing IPv4 Options) recommend to drop these options in 4.3 and 4.4.

References

Affected packages

Azure Linux:3 / kernel

Package

Name
kernel
Purl
pkg:rpm/azure-linux/kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
6.6.143.1-1

Database specific

source
"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-90642.json"