Linux Kernel net-sched /net/sched/cls_fw.c fw_set_parms use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.7$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Linux Kernel. This affects the function fw_set_parms of the file /net/sched/cls_fw.c of the component net-sched. Such manipulation leads to use after free. This vulnerability is documented as CVE-2023-3776. The attack needs to be performed locally. There is not any exploit available. It is best practice to apply a patch to resolve this issue.

Detailsinfo

A vulnerability was found in Linux Kernel (Operating System) (affected version unknown) and classified as critical. Affected by this issue is the function fw_set_parms of the file /net/sched/cls_fw.c of the component net-sched. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation. If tcf_change_indev() fails, fw_set_parms() will immediately return an error after incrementing or decrementing the reference counter in tcf_bind_filter(). If an attacker can control the reference counter and set it to zero, they can cause the reference to be freed, leading to a use-after-free vulnerability. We recommend upgrading past commit 0323bce598eea038714f941ce2b22541c46d488f.

The weakness was released 07/22/2023. The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2023-3776 since 07/19/2023. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 08/22/2024).

Applying a patch is able to eliminate this problem. The bugfix is ready for download at git.kernel.org.

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Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.7

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 7.8
CNA Vector (Google Inc.): 🔍

CVSSv2info

AVACAuCIA
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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: No

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: git.kernel.org

Timelineinfo

07/19/2023 🔍
07/22/2023 +3 days 🔍
07/22/2023 +0 days 🔍
08/22/2024 +397 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-3776 (🔍)
GCVE (CVE): GCVE-0-2023-3776
GCVE (VulDB): GCVE-100-235166

Entryinfo

Created: 07/22/2023 06:55
Updated: 08/22/2024 23:21
Changes: 07/22/2023 06:55 (51), 08/22/2024 23:21 (25)
Complete: 🔍
Cache ID: 216::103

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