Linux Kernel net/sched/sch_qfq.c qfq_dequeue 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 has been found in Linux Kernel and classified as critical. Affected by this vulnerability is the function qfq_dequeue of the file net/sched/sch_qfq.c. Performing a manipulation results in use after free. This vulnerability was named CVE-2023-4921. The attack needs to be approached locally. There is no available exploit. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability was found in Linux Kernel (Operating System) (the affected version unknown). It has been classified as critical. This affects the function qfq_dequeue of the file net/sched/sch_qfq.c. 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:

A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation. When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue(). We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8.

The weakness was presented 09/13/2023. The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2023-4921 since 09/12/2023. 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 08/26/2024).

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

09/12/2023 🔍
09/13/2023 +1 days 🔍
09/13/2023 +0 days 🔍
08/26/2024 +348 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2023-4921 (🔍)
GCVE (CVE): GCVE-0-2023-4921
GCVE (VulDB): GCVE-100-239613

Entryinfo

Created: 09/13/2023 07:04
Updated: 08/26/2024 18:16
Changes: 09/13/2023 07:04 (50), 08/26/2024 18:16 (26)
Complete: 🔍
Cache ID: 216::103

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