Linux Kernel up to 5.10.82/5.15.5 emergency_ctx stack-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.6$0-$5k0.00

A vulnerability was found in Linux Kernel up to 5.10.82/5.15.5. It has been rated as critical. This issue affects the function emergency_ctx. The manipulation with an unknown input leads to a stack-based overflow vulnerability. Using CWE to declare the problem leads to CWE-121. A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: powerpc/32: Fix hardlockup on vmap stack overflow Since the commit c118c7303ad5 ("powerpc/32: Fix vmap stack - Do not activate MMU before reading task struct") a vmap stack overflow results in a hard lockup. This is because emergency_ctx is still addressed with its virtual address allthough data MMU is not active anymore at that time. Fix it by using a physical address instead.

It is possible to read the advisory at git.kernel.org. The identification of this vulnerability is CVE-2021-47567. The exploitation is known to be easy. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 05/24/2024).

Upgrading to version 5.10.83 or 5.15.6 eliminates this vulnerability. Applying the patch dfe906da9a1a/c4e3ff8b8b1d/5bb60ea611db 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 entries VDB-267464, VDB-267465, VDB-267466 and VDB-267467 are related to this item.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔒
VulDB CVSS-BT Score: 🔒
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.6

VulDB Base Score: 8.0
VulDB Temp Score: 7.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Stack-based overflow
CWE: CWE-121 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Local: No
Remote: Partially

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: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.83/5.15.6
Patch: dfe906da9a1a/c4e3ff8b8b1d/5bb60ea611db

Timelineinfo

05/24/2024 Advisory disclosed
05/24/2024 +0 days VulDB entry created
05/24/2024 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2021-47567 (🔒)
See also: 🔒

Entryinfo

Created: 05/24/2024 06:43 PM
Changes: 05/24/2024 06:43 PM (56)
Complete: 🔍
Cache ID: 3:DB3:40

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