Linux Kernel ebpf Verifier kernel/bpf/verifier.c adjust_scalar_min_max_vals dst_reg information exposure

CVSS Meta Temp Score
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Linux Kernel. This issue affects the function adjust_scalar_min_max_vals of the file kernel/bpf/verifier.c of the component ebpf Verifier. The manipulation of the argument dst_reg leads to information exposure. This vulnerability is documented as CVE-2021-4159. The attack can be initiated remotely. There is not any exploit available. Applying a patch is the recommended action to fix this issue.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel (Operating System) (version now known). This issue affects the function adjust_scalar_min_max_vals of the file kernel/bpf/verifier.c of the component ebpf Verifier. The manipulation of the argument dst_reg with an unknown input leads to a information exposure vulnerability. Using CWE to declare the problem leads to CWE-202. When trying to keep information confidential, an attacker can often infer some of the information by using statistics. Impacted is confidentiality. The summary by CVE is:

A vulnerability was found in the Linux kernel's EBPF verifier when handling internal data structures. Internal memory locations could be returned to userspace. A local attacker with the permissions to insert eBPF code to the kernel can use this to leak internal kernel memory details defeating some of the exploit mitigations in place for the kernel.

The weakness was released 08/24/2022. The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2021-4159 since 12/23/2021. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1592 for this issue.

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

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Productinfo

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Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 4.4
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Information exposure
CWE: CWE-202 / CWE-200 / CWE-284
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

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

12/23/2021 🔍
08/24/2022 +243 days 🔍
08/24/2022 +0 days 🔍
09/25/2022 +32 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-4159 (🔍)
GCVE (CVE): GCVE-0-2021-4159
GCVE (VulDB): GCVE-100-207101

Entryinfo

Created: 08/24/2022 22:44
Updated: 09/25/2022 13:28
Changes: 08/24/2022 22:44 (44), 09/25/2022 13:28 (10)
Complete: 🔍
Cache ID: 216::103

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