Upstream information
Description
In the Linux kernel, the following vulnerability has been resolved:xfrm: defensively unhash xfrm_state lists in __xfrm_state_delete
KASAN reproduces a slab-use-after-free in __xfrm_state_delete()'s
hlist_del_rcu calls under syzkaller load on linux-6.12.y stable
(reproduced on 6.12.47, also reachable via the same code path on
torvalds/master and on the ipsec tree). Nine unique signatures cluster
in the xfrm_state lifecycle, the load-bearing one being:
BUG: KASAN: slab-use-after-free in __hlist_del include/linux/list.h:990 [inline]
BUG: KASAN: slab-use-after-free in hlist_del_rcu include/linux/rculist.h:516 [inline]
BUG: KASAN: slab-use-after-free in __xfrm_state_delete net/xfrm/xfrm_state.c
Write of size 8 at addr ffff8881198bcb70 by task kworker/u8:9/435
Workqueue: netns cleanup_net
Call Trace:
__hlist_del / hlist_del_rcu
__xfrm_state_delete
xfrm_state_delete
xfrm_state_flush
xfrm_state_fini
ops_exit_list
cleanup_net
The other observed signatures hit the same slab object from
__xfrm_state_lookup, xfrm_alloc_spi, __xfrm_state_insert and an OOB
write variant of __xfrm_state_delete, all on the byseq/byspi
hash chains.
__xfrm_state_delete() guards its byseq and byspi unhashes with
value-based predicates:
if (x->km.seq)
hlist_del_rcu(&x->byseq);
if (x->id.spi)
hlist_del_rcu(&x->byspi);
while everywhere else in the file (e.g. state_cache, state_cache_input)
the safer hlist_unhashed() check is used. xfrm_alloc_spi() sets
x->id.spi = newspi inside xfrm_state_lock and then immediately inserts
into byspi, but a path that observes x->id.spi != 0 outside of
xfrm_state_lock can still skip-or-hit the byspi unhash inconsistently
with whether x is actually on the list. The same holds for x->km.seq
versus byseq, and the bydst/bysrc unhashes have no predicate at all,
so a second __xfrm_state_delete() on the same object writes through
LIST_POISON pprev.
The defensive change here:
- Use hlist_del_init_rcu() instead of hlist_del_rcu() on bydst,
bysrc, byseq and byspi so a second deletion is a no-op rather
than a write through LIST_POISON pprev. The byseq/byspi nodes
are already initialised in xfrm_state_alloc().
- Test hlist_unhashed() rather than the value predicate for
byseq/byspi, so the unhash decision tracks list state rather than
mutable scalar fields.
Empirical verification: applied this patch on top of v6.12.47, rebuilt,
and re-ran the same syzkaller harness for 1h16m on a previously-crashy
configuration that produced ~100 hits each of slab-use-after-free
Read in xfrm_alloc_spi / Read in __xfrm_state_lookup / Write in
__xfrm_state_delete. After the patch, 7.1M execs across 32 VMs at
~1550 exec/sec produced zero xfrm_state UAF/OOB hits. /proc/slabinfo
confirms the xfrm_state slab is actively allocated and freed during
the run (~143 KiB resident), so the fuzzer is still exercising those
code paths -- they just no longer crash.
Reproduction:
- Linux 6.12.47 x86_64 + KASAN_GENERIC + KASAN_INLINE + KCOV
- syzkaller @ 746545b8b1e4c3a128db8652b340d3df90ce61db
- 32 QEMU/KVM VMs x 2 vCPU on AWS c5.metal bare metal
- 9 unique signatures collected in ~9h, all within xfrm_state
lifecycle
SUSE information
Overall state of this security issue: Pending
This issue is currently rated as having important severity.
| CVSS detail | CNA (NVD) | Linux Kernel CNA | SUSE |
|---|---|---|---|
| Base Score | 7.8 | 7.8 | 7.8 |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| Attack Vector | Local | Local | Local |
| Attack Complexity | Low | Low | Low |
| Privileges Required | Low | Low | Low |
| User Interaction | None | None | None |
| Scope | Unchanged | Unchanged | Unchanged |
| Confidentiality Impact | High | High | High |
| Integrity Impact | High | High | High |
| Availability Impact | High | High | High |
| CVSSv3 Version | 3.1 | 3.1 | 3.1 |
| CVSS detail | SUSE |
|---|---|
| Base Score | 8.5 |
| Vector | CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| Attack Vector | Local |
| Attack Complexity | Low |
| Attack Requirements | None |
| Privileges Required | Low |
| User Interaction | None |
| Vulnerable System Confidentiality Impact | High |
| Vulnerable System Integrity Impact | High |
| Vulnerable System Availability Impact | High |
| Subsequent System Confidentiality Impact | None |
| Subsequent System Integrity Impact | None |
| Subsequent System Availability Impact | None |
| CVSSv4 Version | 4.0 |
Note from the SUSE Security Team on the kernel-default package
SUSE will no longer fix all CVEs in the Linux Kernel anymore, but declare some bug classes as won't fix. Please refer to TID 21496 for more details. SUSE Bugzilla entries: 1267369 [NEW], 1267370 [NEW] No SUSE Security Announcements cross referenced.Status of this issue by product and package
Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.
| Product(s) | Source package | State |
|---|---|---|
| Products under general support and receiving all security fixes. | ||
| SUSE Linux Enterprise Desktop 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise High Availability Extension 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise High Availability Extension 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Live Patching 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Live Patching 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.3 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.3 | kernel-rt | Affected |
| SUSE Linux Enterprise Micro 5.3 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.3 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Micro 5.4 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.4 | kernel-rt | Affected |
| SUSE Linux Enterprise Micro 5.4 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.4 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Micro 5.5 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.5 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.5 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Legacy 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Module for Legacy 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Public Cloud 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Module for Public Cloud 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP7 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Server 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Server 16.0 | kernel-default | Affected |
| SUSE Linux Enterprise Server 16.0 | kernel-source | Affected |
| SUSE Linux Enterprise Server 16.1 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.1 | kernel-source | Affected |
| SUSE Linux Enterprise Workstation Extension 15 SP7 | kernel-default | Affected |
| SUSE Linux Enterprise Workstation Extension 15 SP7 | kernel-source | Affected |
| SUSE Linux Micro 6.0 | kernel-default | Affected |
| SUSE Linux Micro 6.0 | kernel-source | Affected |
| SUSE Linux Micro 6.0 | kernel-source-rt | Affected |
| SUSE Linux Micro 6.1 | kernel-default | Affected |
| SUSE Linux Micro 6.1 | kernel-source | Affected |
| SUSE Linux Micro 6.1 | kernel-source-rt | Affected |
| SUSE Linux Micro 6.2 | kernel-default | Affected |
| SUSE Linux Micro 6.2 | kernel-source | Affected |
| SUSE Real Time Module 15 SP7 | kernel-source-rt | Affected |
| openSUSE Leap 16.0 | kernel-source | Affected |
| Products under Long Term Service Pack support and receiving important and critical security fixes. | ||
| SUSE Linux Enterprise High Performance Computing 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Live Patching 12 SP5 | kernel-default | Affected |
| SUSE Linux Enterprise Live Patching 12 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Live Patching 15 SP4 | kernel-default | Affected |
| SUSE Linux Enterprise Live Patching 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Live Patching 15 SP5 | kernel-default | Affected |
| SUSE Linux Enterprise Live Patching 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | kernel-default | Affected |
| SUSE Linux Enterprise Server 11 SP4 LTSS EXTREME CORE | kernel-source | Affected |
| SUSE Linux Enterprise Server 12 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security | kernel-default | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | kernel-source | Affected |
| SUSE Manager Proxy 4.3 | kernel-source | Affected |
| SUSE Manager Proxy LTS 4.3 | kernel-source | Affected |
| SUSE Manager Retail Branch Server 4.3 | kernel-source | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | kernel-source | Affected |
| SUSE Manager Server 4.3 | kernel-source | Affected |
| SUSE Manager Server LTS 4.3 | kernel-source | Affected |
| Products past their end of life and not receiving proactive updates anymore. | ||
| SUSE CaaS Platform 4.0 | kernel-source | Affected |
| SUSE Enterprise Storage 6 | kernel-source | Affected |
| SUSE Enterprise Storage 7 | kernel-source | Affected |
| SUSE Enterprise Storage 7.1 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 11 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 12 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP5 | kernel-source | Affected |
| SUSE Linux Enterprise Desktop 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | kernel-source | Affected |
| SUSE Linux Enterprise Micro 5.0 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.1 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.2 | kernel-default | Affected |
| SUSE Linux Enterprise Micro 5.2 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Module for Development Tools 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Real Time 15 SP5 | kernel-source-rt | Affected |
| SUSE Linux Enterprise Server 11 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Server 11 SP4-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 12 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Server 12 SP4-ESPOS | kernel-source | Affected |
| SUSE Linux Enterprise Server 12 SP4-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 12 SP4-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | kernel-source | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | kernel-default | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | kernel-source | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | kernel-default | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | kernel-source | Affected |
| SUSE Manager Proxy 4.0 | kernel-source | Affected |
| SUSE Manager Proxy 4.1 | kernel-source | Affected |
| SUSE Manager Proxy 4.2 | kernel-source | Affected |
| SUSE Manager Retail Branch Server 4.0 | kernel-source | Affected |
| SUSE Manager Retail Branch Server 4.1 | kernel-source | Affected |
| SUSE Manager Retail Branch Server 4.2 | kernel-source | Affected |
| SUSE Manager Server 4.0 | kernel-source | Affected |
| SUSE Manager Server 4.1 | kernel-source | Affected |
| SUSE Manager Server 4.2 | kernel-source | Affected |
| SUSE OpenStack Cloud 9 | kernel-source | Affected |
| SUSE OpenStack Cloud Crowbar 9 | kernel-source | Affected |
| SUSE Real Time Module 15 SP4 | kernel-source-rt | Affected |
| SUSE Real Time Module 15 SP5 | kernel-source-rt | Affected |
| openSUSE Leap 15.3 | kernel-source | Affected |
| openSUSE Leap 15.4 | kernel-source | Affected |
| openSUSE Leap 15.4 | kernel-source-rt | Affected |
| openSUSE Leap 15.5 | kernel-source | Affected |
| openSUSE Leap 15.5 | kernel-source-rt | Affected |
| openSUSE Leap 15.6 | kernel-source | Affected |
SUSE Timeline for this CVE
CVE page created: Thu May 28 12:00:14 2026CVE page last modified: Tue Jun 2 19:29:13 2026