Linux Kernel up to 6.2.2 MAY_BACKLOG use after free

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7.7	$0-$5k	0.00

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.2.2 and classified as critical. Affected is the function MAY_BACKLOG. Performing a manipulation results in use after free. This vulnerability was named CVE-2023-53373. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.2.2. This affects the function MAY_BACKLOG. 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: crypto: seqiv - Handle EBUSY correctly As it is seqiv only handles the special return value of EINPROGERSS, which means that in all other cases it will free data related to the request. However, as the caller of seqiv may specify MAY_BACKLOG, we also need to expect EBUSY and treat it in the same way. Otherwise backlogged requests will trigger a use-after-free.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2023-53373 since 09/17/2025. The exploitability is told to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 12/12/2025).

The vulnerability scanner Nessus provides a plugin with the ID 265573 (Linux Distros Unpatched Vulnerability : CVE-2023-53373), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.14.308, 4.19.276, 5.4.235, 5.10.173, 5.15.99, 6.1.16 or 6.2.3 eliminates this vulnerability. Applying the patch cc4d0d4251748a8a68026938f4055d2ac47c5719/1effbddaff60eeef8017c6dea1ee0ed970164d14/63551e4b7cbcd9914258827699eb2cb6ed6e4a16/ae849d2f48019ff9c104e32bf588ccbfb200e971/36ec108b7bd7e280edb22de028467bd09d644620/4d497e8b200a175094e0ac252ed878add39b8771/9477db935eb690f697d9bcc4f608927841bc8b36/32e62025e5e52fbe4812ef044759de7010b15dbc 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 (265573) and CERT Bund (WID-SEC-2025-2092). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

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

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.14.307
• 4.19.275
• 5.4.234
• 5.10.172
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.15.33
• 5.15.34
• 5.15.35
• 5.15.36
• 5.15.37
• 5.15.38
• 5.15.39
• 5.15.40
• 5.15.41
• 5.15.42
• 5.15.43
• 5.15.44
• 5.15.45
• 5.15.46
• 5.15.47
• 5.15.48
• 5.15.49
• 5.15.50
• 5.15.51
• 5.15.52
• 5.15.53
• 5.15.54
• 5.15.55
• 5.15.56
• 5.15.57
• 5.15.58
• 5.15.59
• 5.15.60
• 5.15.61
• 5.15.62
• 5.15.63
• 5.15.64
• 5.15.65
• 5.15.66
• 5.15.67
• 5.15.68
• 5.15.69
• 5.15.70
• 5.15.71
• 5.15.72
• 5.15.73
• 5.15.74
• 5.15.75
• 5.15.76
• 5.15.77
• 5.15.78
• 5.15.79
• 5.15.80
• 5.15.81
• 5.15.82
• 5.15.83
• 5.15.84
• 5.15.85
• 5.15.86
• 5.15.87
• 5.15.88
• 5.15.89
• 5.15.90
• 5.15.91
• 5.15.92
• 5.15.93
• 5.15.94
• 5.15.95
• 5.15.96
• 5.15.97
• 5.15.98
• 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
• 6.2.0
• 6.2.1
• 6.2.2

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: 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

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 265573
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2023-53373

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 4.14.308/4.19.276/5.4.235/5.10.173/5.15.99/6.1.16/6.2.3
Patch: cc4d0d4251748a8a68026938f4055d2ac47c5719/1effbddaff60eeef8017c6dea1ee0ed970164d14/63551e4b7cbcd9914258827699eb2cb6ed6e4a16/ae849d2f48019ff9c104e32bf588ccbfb200e971/36ec108b7bd7e280edb22de028467bd09d644620/4d497e8b200a175094e0ac252ed878add39b8771/9477db935eb690f697d9bcc4f608927841bc8b36/32e62025e5e52fbe4812ef044759de7010b15dbc

Timelineinfo

09/17/2025 CVE reserved
09/18/2025 +1 days Advisory disclosed
09/18/2025 +0 days VulDB entry created
12/12/2025 +85 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-53373 (🔒)
GCVE (CVE): GCVE-0-2023-53373
GCVE (VulDB): GCVE-100-324873
CERT Bund: WID-SEC-2025-2092 - Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Entryinfo

Created: 09/18/2025 16:36
Updated: 12/12/2025 18:25
Changes: 09/18/2025 16:36 (58), 09/20/2025 04:02 (7), 09/20/2025 21:53 (2), 11/29/2025 15:09 (1), 12/12/2025 18:25 (11)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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