NVD / CVE Program· CNA Linux

CVE-2025-38464: tipc: Fix use-after-free in tipc_conn_close().

Noroxi assessment

Priority: Monitor (action score 31/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.21% (FIRST EPSS).
Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: Linux Linux 03dcdd2558e1e55bf843822fe4363dcb48743f2b, 15a6f4971e2f157d57e09ea748d1fbc714277aa4, 1dbf7cd2454a28b1da700085b99346b5445aeabb; azl3 kernel 6.6.96.2-2 on Azure Linux 3.0 6.6.104.2-1; cbl2 kernel 5.15.186.1-1 on CBL Mariner 2.0 5.15.200.1-1.

Low priority for now. Upgrade to Linux Linux 03dcdd2558e1e55bf843822fe4363dcb48743f2b, 15a6f4971e2f157d57e09ea748d1fbc714277aa4, 1dbf7cd2454a28b1da700085b99346b5445aeabb; azl3 kernel 6.6.96.2-2 on Azure Linux 3.0 6.6.104.2-1; cbl2 kernel 5.15.186.1-1 on CBL Mariner 2.0 5.15.200.1-1 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

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

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

Published: Jul 25, 2025
Updated: Aug 5, 2026
EPSS: 0.2% · 12th percentile
CWE: CWE-416

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 31 / 40 · 7.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.2%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: 7.8
CNA · Linux: 7.8; agree

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
linux	linux kernel	cpe:2.3:o:linux:linux_kernel
debian	debian linux	cpe:2.3:o:debian:debian_linux

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

debian debian linux11.0
linux linux kernel5.5 and later · before 5.10.240
linux linux kernel5.11 and later · before 5.15.189
linux linux kernel5.16 and later · before 6.1.146
linux linux kernel3.11 and later · before 5.4.296
linux linux kernel6.7 and later · before 6.12.39
linux linux kernel6.13 and later · before 6.15.7
linux linux kernel6.2 and later · before 6.6.99
linux linux kernel6.16

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

Linux Linux
- 3.11affected
- c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f and later · before 03dcdd2558e1e55bf843822fe4363dcb48743f2baffected · git
- c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f and later · before 15a6f4971e2f157d57e09ea748d1fbc714277aa4affected · git
- c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f and later · before dab8ded2e5ff41012a6ff400b44dbe76ccf3592aaffected · git
- c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f and later · before 1dbf7cd2454a28b1da700085b99346b5445aeabbaffected · git
- c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f and later · before be4b8392da7978294f2f368799d29dd509fb6c4daffected · git
- c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f and later · before 50aa2d121bc2cfe2d825f8a331ea75dfaaab6a50affected · git
- c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f and later · before 3b89e17b2fd64012682bed158d9eb3d2e96dec42affected · git
- c5fa7b3cf3cb22e4ac60485fc2dc187fe012910f and later · before 667eeab4999e981c96b447a4df5f20bdf5c26f13affected · git
- before 3.11not affected · semver

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

Ecosystem	Package	Affected range	Fix
AlmaLinux:10	kernel-abi-stablelists	before 6.12.0-55.30.1.el10_0	6.12.0-55.30.1.el10_0
AlmaLinux:10	kernel-doc	before 6.12.0-55.30.1.el10_0	6.12.0-55.30.1.el10_0
AlmaLinux:8	bpftool	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-abi-stablelists	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-core	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-cross-headers	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-debug	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-debug-core	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-debug-devel	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-debug-modules	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-debug-modules-extra	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-devel	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-doc	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-headers	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-modules	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-modules-extra	before 4.18.0-553.72.1.el8_10	4.18.0-553.72.1.el8_10
AlmaLinux:8	kernel-rt	before 4.18.0-553.72.1.rt7.413.el8_10	4.18.0-553.72.1.rt7.413.el8_10
AlmaLinux:8	kernel-rt-core	before 4.18.0-553.72.1.rt7.413.el8_10	4.18.0-553.72.1.rt7.413.el8_10
AlmaLinux:8	kernel-rt-debug	before 4.18.0-553.72.1.rt7.413.el8_10	4.18.0-553.72.1.rt7.413.el8_10
AlmaLinux:8	kernel-rt-debug-core	before 4.18.0-553.72.1.rt7.413.el8_10	4.18.0-553.72.1.rt7.413.el8_10
AlmaLinux:8	kernel-rt-debug-devel	before 4.18.0-553.72.1.rt7.413.el8_10	4.18.0-553.72.1.rt7.413.el8_10
AlmaLinux:8	kernel-rt-debug-modules	before 4.18.0-553.72.1.rt7.413.el8_10	4.18.0-553.72.1.rt7.413.el8_10
AlmaLinux:8	kernel-rt-debug-modules-extra	before 4.18.0-553.72.1.rt7.413.el8_10	4.18.0-553.72.1.rt7.413.el8_10

+96

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Published before and after this one in the same product

← EarlierCVE-2025-38461Jul 25, 2025 · vsock: Fix transport_* TOCTOU
18Monitor
← EarlierCVE-2025-38463Jul 25, 2025 · tcp: Correct signedness in skb remaining space calculation
22Monitor
Later →CVE-2025-38467Jul 25, 2025 · drm/exynos: exynos7_drm_decon: add vblank check in IRQ handling
22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Linux Linux	03dcdd2558e1e55bf843822fe4363dcb48743f2b	Vendor (CNA)
Linux Linux	15a6f4971e2f157d57e09ea748d1fbc714277aa4	Vendor (CNA)
Linux Linux	1dbf7cd2454a28b1da700085b99346b5445aeabb	Vendor (CNA)
Linux Linux	3b89e17b2fd64012682bed158d9eb3d2e96dec42	Vendor (CNA)
Linux Linux	50aa2d121bc2cfe2d825f8a331ea75dfaaab6a50	Vendor (CNA)
Linux Linux	667eeab4999e981c96b447a4df5f20bdf5c26f13	Vendor (CNA)
Linux Linux	be4b8392da7978294f2f368799d29dd509fb6c4d	Vendor (CNA)
Linux Linux	dab8ded2e5ff41012a6ff400b44dbe76ccf3592a	Vendor (CNA)
azl3 kernel 6.6.96.2-2 on Azure Linux 3.0	6.6.104.2-1 · CBL-Mariner Releases	Microsoft (MSRC)
cbl2 kernel 5.15.186.1-1 on CBL Mariner 2.0	5.15.200.1-1 · CBL-Mariner Releases	Microsoft (MSRC)
almalinux:bpftool	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel-abi-stablelists	6.12.0-55.30.1.el10_0 · AlmaLinux:10	Package registry (OSV)
almalinux:kernel-core	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel-cross-headers	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel-debug	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel-debug-core	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel-debug-devel	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel-debug-modules	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel-debug-modules-extra	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel-devel	4.18.0-553.72.1.el8_10 · AlmaLinux:8	Package registry (OSV)
almalinux:kernel-doc	6.12.0-55.30.1.el10_0 · AlmaLinux:10	Package registry (OSV)
debian:linux	6.1.147-1 · Debian:12	Package registry (OSV)
red hat:bpftool	0:4.18.0-477.108.1.el8_8 · Red Hat:rhel_e4s:8.8::baseos	Package registry (OSV)
red hat:bpftool-debuginfo	0:4.18.0-477.108.1.el8_8 · Red Hat:rhel_e4s:8.8::baseos	Package registry (OSV)
red hat:kernel	0:4.18.0-477.108.1.el8_8 · Red Hat:rhel_e4s:8.8::baseos	Package registry (OSV)
red hat:kernel-abi-stablelists	0:4.18.0-477.108.1.el8_8 · Red Hat:rhel_e4s:8.8::baseos	Package registry (OSV)
red hat:kernel-core	0:4.18.0-477.108.1.el8_8 · Red Hat:rhel_e4s:8.8::baseos	Package registry (OSV)
red hat:kernel-debug	0:4.18.0-477.108.1.el8_8 · Red Hat:rhel_e4s:8.8::baseos	Package registry (OSV)
red hat:kernel-debug-core	0:4.18.0-477.108.1.el8_8 · Red Hat:rhel_e4s:8.8::baseos	Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Someone with local access to the system can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Local
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-416 · Use After Free

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Root cause

After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.

The bug in code

The whole CWE-416 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1free(dev->buf);
2/* ... another thread is still running ... */
3process(dev->buf);

Fixed

1lock(&dev->lock);
2free(dev->buf);
3dev->buf = NULL;
4unlock(&dev->lock);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

Fix✗ → ✓Sep 28, 2026, 10:08 PM UTC

For records you follow, these changes also arrive as notifications. →

References

git.kernel.org/stable/c/03dcdd2558e1e55bf843822fe4363dcb48743f2b

Show all references (9 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records