ipv6: Fix dst leak for uncached routes.
In the Linux kernel, the following vulnerability has been resolved: ipv6: Fix dst leak for uncached routes. ip6_route_output_flags(), ip6_rt_put_flags(), and ip6_dst_check() detect an uncached route by list_empty(&rt->dst.rt_uncached), which replaced the static DST_NOCACHE flag check in commit a4c2fd7f7891 ("net: remove DST_NOCACHE flag"). When a device is unregistered, rt6_uncached_list_flush_dev() unlinks uncached routes tied to the device from rt6_uncached_list. Previously, they were moved to another list with list_move() (__list_del_entry() + list_add()), and since commit 98aa546af5e4 ("inet: remove (struct uncached_list)->quarantine"), the routes are just unlinked with list_del_init(). If list_del_init() runs concurrently, list_empty() evaluates to true; ip6_route_output_flags() calls dst_hold_safe() incorrectly and ip6_rt_put_flags() skips ip6_rt_put(), leaking dst, and thus dev tied via rt->from as well. The same race is partially fixed by commit 9a6f0c4d5796 ("dst: fix races in rt6_uncached_list_del() and rt_del_uncached_list()"). Let's check rt6->dst.rt_uncached_list instead. Note that IPv4 does not have the same issue.
CVE-2026-98596
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-98596
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "98aa546af5e4f180439c82da403cc77926d3953b",
"lessThan": "5045aa25f3790dcdb158a58ac60ccf8da42959aa",
"versionType": "git"
},
{
"status": "affected",
"version": "98aa546af5e4f180439c82da403cc77926d3953b",
"lessThan": "ed902d5546fb9c142b3216d8eec914fa1bc0aa80",
"versionType": "git"
},
{
"status": "affected",
"version": "98aa546af5e4f180439c82da403cc77926d3953b",
"lessThan": "f9722746df13a8a29103c847ef56b02c11ce0963",
"versionType": "git"
},
{
"status": "affected",
"version": "98aa546af5e4f180439c82da403cc77926d3953b",
"lessThan": "be31fe6333f534155e6b408f1ef6d77974bb41aa",
"versionType": "git"
}
],
"programFiles": [
"include/net/ip6_route.h",
"net/ipv6/route.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.11"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.11",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.12.112",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.55",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.2.9",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"include/net/ip6_route.h",
"net/ipv6/route.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-98596
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #38618 · Revision 1
- Added to Heist Feed
- Publisher date