NVD / CVE Program· CNA Linux

CVE-2024-56642: tipc: Fix use-after-free of kernel socket in cleanup_bearer().

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: 0.24% (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 4e69457f9dfae67435f3ccf29008768eae860415, 5.10.231, 5.13; azl3 kernel 6.6.64.2-9 on Azure Linux 3.0 6.6.76.1-1; azl3 kernel 6.6.76.1-1 on Azure Linux 3.0 6.6.76.1-1.

Low priority for now. Upgrade to Linux Linux 4e69457f9dfae67435f3ccf29008768eae860415, 5.10.231, 5.13; azl3 kernel 6.6.64.2-9 on Azure Linux 3.0 6.6.76.1-1; azl3 kernel 6.6.76.1-1 on Azure Linux 3.0 6.6.76.1-1 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 of kernel socket in cleanup_bearer(). syzkaller reported a use-after-free of UDP kernel socket in cleanup_bearer() without repro. [0][1] When bearer_disable() calls tipc_udp_disable(), cleanup of the UDP kernel socket is deferred by work calling cleanup_bearer(). tipc_exit_net() waits for such works to finish by checking tipc_net(net)->wq_count. However, the work decrements the count too early before releasing the kernel socket, unblocking cleanup_net() and resulting in use-after-free. Let's move the decrement after releasing the socket in cleanup_bearer(). [0]: ref_tracker: net notrefcnt@000000009b3d1faf has 1/1 users at sk_alloc+0x438/0x608 inet_create+0x4c8/0xcb0 __sock_create+0x350/0x6b8 sock_create_kern+0x58/0x78 udp_sock_create4+0x68/0x398 udp_sock_create+0x88/0xc8 tipc_udp_enable+0x5e8/0x848 __tipc_nl_bearer_enable+0x84c/0xed8 tipc_nl_bearer_enable+0x38/0x60 genl_family_rcv_msg_doit+0x170/0x248 genl_rcv_msg+0x400/0x5b0 netlink_rcv_skb+0x1dc/0x398 genl_rcv+0x44/0x68 netlink_unicast+0x678/0x8b0 netlink_sendmsg+0x5e4/0x898 ____sys_sendmsg+0x500/0x830 [1]: BUG: KMSAN: use-after-free in udp_hashslot include/net/udp.h:85 [inline] BUG: KMSAN: use-after-free in udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979 udp_hashslot include/net/udp.h:85 [inline] udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979 sk_common_release+0xaf/0x3f0 net/core/sock.c:3820 inet_release+0x1e0/0x260 net/ipv4/af_inet.c:437 inet6_release+0x6f/0xd0 net/ipv6/af_inet6.c:489 __sock_release net/socket.c:658 [inline] sock_release+0xa0/0x210 net/socket.c:686 cleanup_bearer+0x42d/0x4c0 net/tipc/udp_media.c:819 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xcaf/0x1c90 kernel/workqueue.c:3310 worker_thread+0xf6c/0x1510 kernel/workqueue.c:3391 kthread+0x531/0x6b0 kernel/kthread.c:389 ret_from_fork+0x60/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244 Uninit was created at: slab_free_hook mm/slub.c:2269 [inline] slab_free mm/slub.c:4580 [inline] kmem_cache_free+0x207/0xc40 mm/slub.c:4682 net_free net/core/net_namespace.c:454 [inline] cleanup_net+0x16f2/0x19d0 net/core/net_namespace.c:647 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xcaf/0x1c90 kernel/workqueue.c:3310 worker_thread+0xf6c/0x1510 kernel/workqueue.c:3391 kthread+0x531/0x6b0 kernel/kthread.c:389 ret_from_fork+0x60/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:244 CPU: 0 UID: 0 PID: 54 Comm: kworker/0:2 Not tainted 6.12.0-rc1-00131-gf66ebf37d69c #7 91723d6f74857f70725e1583cba3cf4adc716cfa Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014 Workqueue: events cleanup_bearer

HighCVSS 7.8 · v3.1—No exploit Fix available

Memory safety

Published: Dec 27, 2024
Updated: Aug 5, 2026
EPSS: 0.2% · 15th percentile
CWE: CWE-416

Report tools

JSON

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

If any of these changes, we'll tell you in the daily email digest.

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

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.

We use this product, ask for help

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.

ProductVersion

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

Affected versions

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

linux linux kernel4.2 and later · before 5.4.287
linux linux kernel5.5 and later · before 5.10.231
linux linux kernel5.11 and later · before 5.15.174
linux linux kernel5.16 and later · before 6.1.120
linux linux kernel6.2 and later · before 6.6.66
linux linux kernel6.7 and later · before 6.12.5
linux linux kernel6.13

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
- b9f5b7ad4ac3af006443f535b1ce7bff1d130d7d, 5.13affected
- d1f76dfadaf8f47ed1753f97dbcbd41c16215ffa and later · before 4e69457f9dfae67435f3ccf29008768eae860415affected · git
- 5195ec5e365a2a9331bfeb585b613a6e94f98dba and later · before 650ee9a22d7a2de8999fac2d45983597a0c22359affected · git
- 04c26faa51d1e2fe71cf13c45791f5174c37f986 and later · before d2a4894f238551eae178904e7f45af87577074fdaffected · git
- 04c26faa51d1e2fe71cf13c45791f5174c37f986 and later · before d62d5180c036eeac09f80660edc7a602b369125faffected · git
- 04c26faa51d1e2fe71cf13c45791f5174c37f986 and later · before d00d4470bf8c4282617a3a10e76b20a9c7e4cffaaffected · git
- 04c26faa51d1e2fe71cf13c45791f5174c37f986 and later · before e48b211c4c59062cb6dd6c2c37c51a7cc235a464affected · git
- 04c26faa51d1e2fe71cf13c45791f5174c37f986 and later · before 6a2fa13312e51a621f652d522d7e2df7066330b6affected · git
- 5.4.124 and later · before 5.4.287affected · semver
- 5.10.42 and later · before 5.10.231affected · semver

Package-level exposure

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

Ecosystem	Package	Affected range	Fix
Debian:12	linux	before 6.1.123-1	6.1.123-1
Debian:13	linux	before 6.12.5-1	6.12.5-1
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	kernel-64kb	before 5.3.18-150300.59.204.1	5.3.18-150300.59.204.1
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	kernel-default-base	before 5.3.18-150300.59.204.1.150300.18.122.1	5.3.18-150300.59.204.1.150300.18.122.1
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	kernel-docs	before 5.3.18-150300.59.204.1	5.3.18-150300.59.204.1
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	kernel-obs-build	before 5.3.18-150300.59.204.1	5.3.18-150300.59.204.1
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	kernel-preempt	before 5.3.18-150300.59.204.1	5.3.18-150300.59.204.1
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	kernel-source	before 5.3.18-150300.59.204.1	5.3.18-150300.59.204.1
SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	kernel-syms	before 5.3.18-150300.59.204.1	5.3.18-150300.59.204.1
SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS	kernel-64kb	before 5.14.21-150400.24.150.1	5.14.21-150400.24.150.1
SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS	kernel-docs	before 5.14.21-150400.24.150.1	5.14.21-150400.24.150.1
SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS	kernel-obs-build	before 5.14.21-150400.24.150.1	5.14.21-150400.24.150.1
SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS	kernel-source	before 5.14.21-150400.24.150.1	5.14.21-150400.24.150.1
SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS	kernel-syms	before 5.14.21-150400.24.150.1	5.14.21-150400.24.150.1
SUSE:Linux Enterprise Live Patching 15 SP3	kernel-default	before 5.3.18-150300.59.204.1	5.3.18-150300.59.204.1
SUSE:Linux Enterprise Live Patching 15 SP3	kernel-livepatch-SLE15-SP3_Update_57	before 1-150300.7.3.1	1-150300.7.3.1
SUSE:Linux Enterprise Live Patching 15 SP4	kernel-livepatch-SLE15-SP4_Update_36	before 1-150400.9.3.1	1-150400.9.3.1
SUSE:Linux Enterprise Micro 5.1	kernel-rt	before 5.3.18-150300.208.1	5.3.18-150300.208.1
SUSE:Linux Enterprise Micro 5.1	kernel-source-rt	before 5.3.18-150300.208.1	5.3.18-150300.208.1
SUSE:Linux Enterprise Micro 5.3	kernel-default	before 5.14.21-150400.24.150.1	5.14.21-150400.24.150.1
SUSE:Linux Enterprise Micro 5.3	kernel-default-base	before 5.14.21-150400.24.150.1.150400.24.74.1	5.14.21-150400.24.150.1.150400.24.74.1
SUSE:Linux Enterprise Micro 5.3	kernel-rt	before 5.14.21-150400.15.109.1	5.14.21-150400.15.109.1
SUSE:Linux Enterprise Micro 5.3	kernel-source-rt	before 5.14.21-150400.15.109.1	5.14.21-150400.15.109.1
SUSE:Linux Enterprise Server 15 SP3-LTSS	kernel-zfcpdump	before 5.3.18-150300.59.204.1	5.3.18-150300.59.204.1

Same product

linux: all records

Other highest-scoring records for the same primary product.

CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
90Now
CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
89Now
CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
85Now

Published before and after this one in the same product

← EarlierCVE-2024-56639Dec 27, 2024 · net: hsr: must allocate more bytes for RedBox support
22Monitor
← EarlierCVE-2024-56640Dec 27, 2024 · net/smc: fix LGR and link use-after-free issue
31Monitor
Later →CVE-2024-56643Dec 27, 2024 · dccp: Fix memory leak in dccp_feat_change_recv
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	4e69457f9dfae67435f3ccf29008768eae860415	Vendor (CNA)
Linux Linux	5.10.231	Vendor (CNA)
Linux Linux	5.13	Vendor (CNA)
Linux Linux	5.4.287	Vendor (CNA)
Linux Linux	650ee9a22d7a2de8999fac2d45983597a0c22359	Vendor (CNA)
Linux Linux	6a2fa13312e51a621f652d522d7e2df7066330b6	Vendor (CNA)
Linux Linux	d00d4470bf8c4282617a3a10e76b20a9c7e4cffa	Vendor (CNA)
Linux Linux	d2a4894f238551eae178904e7f45af87577074fd	Vendor (CNA)
Linux Linux	d62d5180c036eeac09f80660edc7a602b369125f	Vendor (CNA)
Linux Linux	e48b211c4c59062cb6dd6c2c37c51a7cc235a464	Vendor (CNA)
azl3 kernel 6.6.64.2-9 on Azure Linux 3.0	6.6.76.1-1 · CBL-Mariner Releases	Microsoft (MSRC)
azl3 kernel 6.6.76.1-1 on Azure Linux 3.0	6.6.76.1-1 · CBL-Mariner Releases	Microsoft (MSRC)
cbl2 kernel 5.15.173.1-2 on CBL Mariner 2.0	5.15.176.3-1 · CBL-Mariner Releases	Microsoft (MSRC)
cbl2 kernel 5.15.173.1-2 on CBL-Mariner 2.0	5.15.176.3-1 · CBL-Mariner Releases	Microsoft (MSRC)
cbl2 kernel 5.15.176.3-1 on CBL Mariner 2.0	5.15.176.3-1 · CBL-Mariner Releases	Microsoft (MSRC)
debian:linux	6.1.123-1 · Debian:12	Package registry (OSV)
suse:kernel-64kb	5.3.18-150300.59.204.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	Package registry (OSV)
suse:kernel-default	5.3.18-150300.59.204.1 · SUSE:Linux Enterprise Live Patching 15 SP3	Package registry (OSV)
suse:kernel-default-base	5.3.18-150300.59.204.1.150300.18.122.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	Package registry (OSV)
suse:kernel-docs	5.3.18-150300.59.204.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	Package registry (OSV)
suse:kernel-livepatch-SLE15-SP3_Update_57	1-150300.7.3.1 · SUSE:Linux Enterprise Live Patching 15 SP3	Package registry (OSV)
suse:kernel-obs-build	5.3.18-150300.59.204.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	Package registry (OSV)
suse:kernel-preempt	5.3.18-150300.59.204.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	Package registry (OSV)
suse:kernel-rt	5.14.21-150400.15.109.1 · SUSE:Linux Enterprise Micro 5.3	Package registry (OSV)
suse:kernel-source	5.3.18-150300.59.204.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	Package registry (OSV)
suse:kernel-source-rt	5.14.21-150400.15.109.1 · SUSE:Linux Enterprise Micro 5.3	Package registry (OSV)
suse:kernel-syms	5.3.18-150300.59.204.1 · SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS	Package registry (OSV)
suse:kernel-zfcpdump	5.3.18-150300.59.204.1 · SUSE:Linux Enterprise Server 15 SP3-LTSS	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, 10:09 PM UTC

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

References

git.kernel.org/stable/c/4e69457f9dfae67435f3ccf29008768eae860415

Show all references (8 more)

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

All records