Linux Kernel up to 6.16-rc5 tipc tipc_conn_close use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 6.16-rc5. This issue affects the function tipc_conn_close of the component tipc. Performing a manipulation results in use after free. This vulnerability is cataloged as CVE-2025-38464. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 6.16-rc5. This affects the function tipc_conn_close of the component tipc. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: tipc: Fix use-after-free in tipc_conn_close(). syzbot reported a null-ptr-deref in tipc_conn_close() during netns dismantle. [0] tipc_topsrv_stop() iterates tipc_net(net)->topsrv->conn_idr and calls tipc_conn_close() for each tipc_conn. The problem is that tipc_conn_close() is called after releasing the IDR lock. At the same time, there might be tipc_conn_recv_work() running and it could call tipc_conn_close() for the same tipc_conn and release its last ->kref. Once we release the IDR lock in tipc_topsrv_stop(), there is no guarantee that the tipc_conn is alive. Let's hold the ref before releasing the lock and put the ref after tipc_conn_close() in tipc_topsrv_stop(). [0]: BUG: KASAN: use-after-free in tipc_conn_close+0x122/0x140 net/tipc/topsrv.c:165 Read of size 8 at addr ffff888099305a08 by task kworker/u4:3/435 CPU: 0 PID: 435 Comm: kworker/u4:3 Not tainted 4.19.204-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 tipc_conn_close+0x122/0x140 net/tipc/topsrv.c:165 tipc_topsrv_stop net/tipc/topsrv.c:701 [inline] tipc_topsrv_exit_net+0x27b/0x5c0 net/tipc/topsrv.c:722 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:553 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Allocated by task 23: kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] kzalloc include/linux/slab.h:709 [inline] tipc_conn_alloc+0x43/0x4f0 net/tipc/topsrv.c:192 tipc_topsrv_accept+0x1b5/0x280 net/tipc/topsrv.c:470 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Freed by task 23: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 tipc_conn_kref_release net/tipc/topsrv.c:150 [inline] kref_put include/linux/kref.h:70 [inline] conn_put+0x2cd/0x3a0 net/tipc/topsrv.c:155 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 The buggy address belongs to the object at ffff888099305a00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 8 bytes inside of 512-byte region [ffff888099305a00, ffff888099305c00) The buggy address belongs to the page: page:ffffea000264c140 count:1 mapcount:0 mapping:ffff88813bff0940 index:0x0 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea00028b6b88 ffffea0002cd2b08 ffff88813bff0940 raw: 0000000000000000 ffff888099305000 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888099305900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888099305980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888099305a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888099305a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888099305b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-38464 since 04/16/2025. The exploitability is told to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 01/04/2026).

The vulnerability scanner Nessus provides a plugin with the ID 261195 (Oracle Linux 9 : kernel (ELSA-2025-15011)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.296, 5.10.240, 5.15.189, 6.1.146, 6.6.99, 6.12.39, 6.15.7 or 6.16-rc6 eliminates this vulnerability. Applying the patch 03dcdd2558e1e55bf843822fe4363dcb48743f2b/15a6f4971e2f157d57e09ea748d1fbc714277aa4/dab8ded2e5ff41012a6ff400b44dbe76ccf3592a/1dbf7cd2454a28b1da700085b99346b5445aeabb/be4b8392da7978294f2f368799d29dd509fb6c4d/50aa2d121bc2cfe2d825f8a331ea75dfaaab6a50/3b89e17b2fd64012682bed158d9eb3d2e96dec42/667eeab4999e981c96b447a4df5f20bdf5c26f13 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.

The vulnerability is also documented in the databases at Tenable (261195), EUVD (EUVD-2025-22677) and CERT Bund (WID-SEC-2025-1653). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • IBM QRadar SIEM
  • SUSE openSUSE
  • RESF Rocky Linux
  • Dell Avamar
  • Open Source Linux Kernel
  • Dell NetWorker
  • Dell Secure Connect Gateway

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.9
VulDB Meta Temp Score: 7.7

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 261195
Nessus Name: Oracle Linux 9 : kernel (ELSA-2025-15011)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.4.296/5.10.240/5.15.189/6.1.146/6.6.99/6.12.39/6.15.7/6.16-rc6
Patch: 03dcdd2558e1e55bf843822fe4363dcb48743f2b/15a6f4971e2f157d57e09ea748d1fbc714277aa4/dab8ded2e5ff41012a6ff400b44dbe76ccf3592a/1dbf7cd2454a28b1da700085b99346b5445aeabb/be4b8392da7978294f2f368799d29dd509fb6c4d/50aa2d121bc2cfe2d825f8a331ea75dfaaab6a50/3b89e17b2fd64012682bed158d9eb3d2e96dec42/667eeab4999e981c96b447a4df5f20bdf5c26f13

Timelineinfo

04/16/2025 CVE reserved
07/25/2025 +100 days Advisory disclosed
07/25/2025 +0 days VulDB entry created
01/04/2026 +162 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-38464 (🔒)
GCVE (CVE): GCVE-0-2025-38464
GCVE (VulDB): GCVE-100-317739
EUVD: 🔒
CERT Bund: WID-SEC-2025-1653 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 07/25/2025 19:31
Updated: 01/04/2026 00:15
Changes: 07/25/2025 19:31 (59), 07/28/2025 07:58 (1), 07/30/2025 04:17 (1), 08/22/2025 22:44 (7), 09/04/2025 11:53 (2), 09/15/2025 05:37 (1), 09/29/2025 02:26 (1), 11/02/2025 13:58 (1), 12/22/2025 21:09 (11), 01/04/2026 00:15 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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