Linux Kernel up to 6.2.10 net/sctp/sm_sideeffect.c wait_for_sndbuf null pointer dereference

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5.0	$0-$5k	0.00

Summaryinfo

A vulnerability described as critical has been identified in Linux Kernel up to 6.2.10. The impacted element is the function wait_for_sndbuf of the file net/sctp/sm_sideeffect.c. Executing a manipulation can lead to null pointer dereference. The identification of this vulnerability is CVE-2023-53296. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 6.2.10 and classified as critical. This vulnerability affects the function wait_for_sndbuf of the file net/sctp/sm_sideeffect.c. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: sctp: check send stream number after wait_for_sndbuf This patch fixes a corner case where the asoc out stream count may change after wait_for_sndbuf. When the main thread in the client starts a connection, if its out stream count is set to N while the in stream count in the server is set to N - 2, another thread in the client keeps sending the msgs with stream number N - 1, and waits for sndbuf before processing INIT_ACK. However, after processing INIT_ACK, the out stream count in the client is shrunk to N - 2, the same to the in stream count in the server. The crash occurs when the thread waiting for sndbuf is awake and sends the msg in a non-existing stream(N - 1), the call trace is as below: KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] Call Trace: <TASK> sctp_cmd_send_msg net/sctp/sm_sideeffect.c:1114 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1777 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] sctp_do_sm+0x197d/0x5310 net/sctp/sm_sideeffect.c:1170 sctp_primitive_SEND+0x9f/0xc0 net/sctp/primitive.c:163 sctp_sendmsg_to_asoc+0x10eb/0x1a30 net/sctp/socket.c:1868 sctp_sendmsg+0x8d4/0x1d90 net/sctp/socket.c:2026 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:825 sock_sendmsg_nosec net/socket.c:722 [inline] sock_sendmsg+0xde/0x190 net/socket.c:745 The fix is to add an unlikely check for the send stream number after the thread wakes up from the wait_for_sndbuf.

The advisory is shared for download at git.kernel.org. This vulnerability was named CVE-2023-53296 since 09/16/2025. The exploitation appears to be difficult. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 265229 (Linux Distros Unpatched Vulnerability : CVE-2023-53296), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.19.281, 5.4.241, 5.10.178, 5.15.107, 6.1.24 or 6.2.11 eliminates this vulnerability. Applying the patch 9346a1a21142357972a6f466ba6275ddc54b04ac/0443fff49d6352160c200064156c25898bd9f58c/b4b6dfad41aaae9e36e44327b18d5cf4b20dd2ce/667eb99cf7c15fe5b0ecefe75cf658e20ef20c9f/d2128636b303aa9cf065055402ee6697409a8837/a615e7270318fa0b98bf1ff38daf6cf52d840312/2584024b23552c00d95b50255e47bd18d306d31a 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 (265229) and CERT Bund (WID-SEC-2025-2053). Once again VulDB remains the best source for vulnerability data.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• IBM QRadar SIEM
• SUSE openSUSE
• Open Source Linux Kernel
• RESF Rocky Linux
• Dell Secure Connect Gateway
• F5 F5OS

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.19.280
• 5.4.240
• 5.10.177
• 5.15.106
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.2.0
• 6.2.1
• 6.2.2
• 6.2.3
• 6.2.4
• 6.2.5
• 6.2.6
• 6.2.7
• 6.2.8
• 6.2.9
• 6.2.10

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 5.0

VulDB Base Score: 4.8
VulDB Temp Score: 4.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔒

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 265229
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-53296

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 4.19.281/5.4.241/5.10.178/5.15.107/6.1.24/6.2.11
Patch: 9346a1a21142357972a6f466ba6275ddc54b04ac/0443fff49d6352160c200064156c25898bd9f58c/b4b6dfad41aaae9e36e44327b18d5cf4b20dd2ce/667eb99cf7c15fe5b0ecefe75cf658e20ef20c9f/d2128636b303aa9cf065055402ee6697409a8837/a615e7270318fa0b98bf1ff38daf6cf52d840312/2584024b23552c00d95b50255e47bd18d306d31a

Timelineinfo

09/16/2025 Advisory disclosed
09/16/2025 +0 days CVE reserved
09/16/2025 +0 days VulDB entry created
01/11/2026 +117 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-53296 (🔒)
GCVE (CVE): GCVE-0-2023-53296
GCVE (VulDB): GCVE-100-324364
CERT Bund: WID-SEC-2025-2053 - Linux Kernel: Mehrere Schwachstellen

Entryinfo

Created: 09/16/2025 13:54
Updated: 01/11/2026 11:20
Changes: 09/16/2025 13:54 (60), 09/19/2025 15:14 (2), 12/03/2025 04:12 (12), 01/02/2026 12:54 (7), 01/11/2026 11:20 (1)
Complete: 🔍
Cache ID: 216::103

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