ipv6: flowlabel: cap duplicate leases per socket
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.6.160, 6.12.112, 6.18.53, 7.2.7
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: ipv6: flowlabel: cap duplicate leases per socket ipv6_flowlabel_get() allocates an ipv6_fl_socklist entry for every successful GET. The recheck path for a compatible existing flowlabel links another lease without applying any lease admission check. Repeated GET requests for one shareable label can therefore grow a socket's lease list without bound. Reject a new unprivileged lease once the socket already holds FL_MAX_PER_SOCK leases. Check this on the shared recheck path so reuse of a globally interned label, including the fl_intern() collision path, is covered as well. New-label admission remains under the existing mem_check() policy. Use capable(CAP_NET_ADMIN) rather than ns_capable(), matching mem_check(). An unprivileged user must not bypass the cap by creating a user namespace and a netns where they have CAP_NET_ADMIN, which would still consume host memory. Check the capability only when the socket reaches the limit, so successful unprivileged GET requests below the cap do not generate a capability audit. Do the admission check before updating linger and expires so a rejected GET does not refresh the shared label, matching the existing socket-list allocation failure path.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 0159f716d8adbe85951cdf008d0afe27d874eaa6; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 6d917992c22b6029fc2dc1bd464b7f6709357161; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 2f1a6dd5c80ceb902f50449efe899f29cd7918e3; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 467467bf4209f9f8add0c648bae763f92a0224c3; From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 · fixed in 8d6cd188508513503805c156165de38e4e4a8615
- Linux Linux
2.6.12
- KernelLinux
From 2.6.12 · fixed in 6.6.160; From 6.7.0 · fixed in 6.12.112; From 6.13.0 · fixed in 6.18.53; From 6.19.0 · fixed in 7.2.7