Linux Kernel up to 6.16-rc2 net/atm/lec.c lecd_attach dev_lec 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 classified as critical has been found in Linux Kernel up to 6.16-rc2. This impacts the function lecd_attach of the file net/atm/lec.c. Performing a manipulation of the argument dev_lec results in use after free. This vulnerability is identified as CVE-2025-38323. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.16-rc2. It has been classified as critical. This affects the function lecd_attach of the file net/atm/lec.c. The manipulation of the argument dev_lec 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: net: atm: add lec_mutex syzbot found its way in net/atm/lec.c, and found an error path in lecd_attach() could leave a dangling pointer in dev_lec[]. Add a mutex to protect dev_lecp[] uses from lecd_attach(), lec_vcc_attach() and lec_mcast_attach(). Following patch will use this mutex for /proc/net/atm/lec. BUG: KASAN: slab-use-after-free in lecd_attach net/atm/lec.c:751 [inline] BUG: KASAN: slab-use-after-free in lane_ioctl+0x2224/0x23e0 net/atm/lec.c:1008 Read of size 8 at addr ffff88807c7b8e68 by task syz.1.17/6142 CPU: 1 UID: 0 PID: 6142 Comm: syz.1.17 Not tainted 6.16.0-rc1-syzkaller-00239-g08215f5486ec #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xcd/0x680 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 lecd_attach net/atm/lec.c:751 [inline] lane_ioctl+0x2224/0x23e0 net/atm/lec.c:1008 do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159 sock_do_ioctl+0x118/0x280 net/socket.c:1190 sock_ioctl+0x227/0x6b0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Allocated by task 6132: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kvmalloc_node_noprof+0x27b/0x620 mm/slub.c:5015 alloc_netdev_mqs+0xd2/0x1570 net/core/dev.c:11711 lecd_attach net/atm/lec.c:737 [inline] lane_ioctl+0x17db/0x23e0 net/atm/lec.c:1008 do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159 sock_do_ioctl+0x118/0x280 net/socket.c:1190 sock_ioctl+0x227/0x6b0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6132: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x2b4/0x4d0 mm/slub.c:4842 free_netdev+0x6c5/0x910 net/core/dev.c:11892 lecd_attach net/atm/lec.c:744 [inline] lane_ioctl+0x1ce8/0x23e0 net/atm/lec.c:1008 do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159 sock_do_ioctl+0x118/0x280 net/socket.c:1190 sock_ioctl+0x227/0x6b0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893

It is possible to read the advisory at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-38323 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 12/19/2025).

The vulnerability scanner Nessus provides a plugin with the ID 253428 (SUSE SLES15 Security Update : kernel (SUSE-SU-2025:02923-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.4.295, 5.10.239, 5.15.186, 6.1.142, 6.6.95, 6.12.35, 6.15.4 or 6.16-rc3 eliminates this vulnerability. Applying the patch e91274cc7ed88ab5bdc62d426067c82b0b118a0b/a7a713dfb5f9477345450f27c7c0741864511192/17e156a94e94a906a570dbf9b48877956c60bef8/18e8f0c4f826fb08c2d3825cdd6c57e24b207e0a/dffd03422ae6a459039c8602f410e6c0f4cbc6c8/f4d80b16ecc4229f7e6345158ef34c36be323f0e/64b378db28a967f7b271b055380c2360279aa424/d13a3824bfd2b4774b671a75cf766a16637a0e67 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 (253428), EUVD (EUVD-2025-20923) and CERT Bund (WID-SEC-2025-1522). Be aware that VulDB is the high quality source for vulnerability data.

Affected

  • Google Container-Optimized OS
  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • IBM QRadar SIEM
  • SUSE openSUSE
  • RESF Rocky Linux
  • Open Source Linux Kernel
  • Dell Avamar
  • Dell NetWorker

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
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
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: 🔒

0-DayUnlockUnlockUnlockUnlock
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Nessus ID: 253428
Nessus Name: SUSE SLES15 Security Update : kernel (SUSE-SU-2025:02923-1)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.4.295/5.10.239/5.15.186/6.1.142/6.6.95/6.12.35/6.15.4/6.16-rc3
Patch: e91274cc7ed88ab5bdc62d426067c82b0b118a0b/a7a713dfb5f9477345450f27c7c0741864511192/17e156a94e94a906a570dbf9b48877956c60bef8/18e8f0c4f826fb08c2d3825cdd6c57e24b207e0a/dffd03422ae6a459039c8602f410e6c0f4cbc6c8/f4d80b16ecc4229f7e6345158ef34c36be323f0e/64b378db28a967f7b271b055380c2360279aa424/d13a3824bfd2b4774b671a75cf766a16637a0e67

Timelineinfo

04/16/2025 CVE reserved
07/10/2025 +85 days Advisory disclosed
07/10/2025 +0 days VulDB entry created
12/19/2025 +162 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2025-38323 (🔒)
GCVE (CVE): GCVE-0-2025-38323
GCVE (VulDB): GCVE-100-315951
EUVD: 🔒
CERT Bund: WID-SEC-2025-1522 - Linux Kernel: Mehrere Schwachstellen erm&ouml;glichen Denial of Service

Entryinfo

Created: 07/10/2025 11:33
Updated: 12/19/2025 18:43
Changes: 07/10/2025 11:33 (60), 07/10/2025 15:39 (1), 08/23/2025 23:33 (2), 10/11/2025 21:02 (7), 11/02/2025 19:43 (1), 12/08/2025 00:33 (1), 12/19/2025 18:43 (13)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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