Linux Kernel up to 5.10.82/5.15.5 netif_carrier_on/netif_carrier_off null pointer dereference

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.5$0-$5k0.00

A vulnerability classified as critical was found in Linux Kernel up to 5.10.82/5.15.5. Affected by this vulnerability is the function netif_carrier_on/netif_carrier_off. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: mlxsw: spectrum: Protect driver from buggy firmware When processing port up/down events generated by the device's firmware, the driver protects itself from events reported for non-existent local ports, but not the CPU port (local port 0), which exists, but lacks a netdev. This can result in a NULL pointer dereference when calling netif_carrier_{on,off}(). Fix this by bailing early when processing an event reported for the CPU port. Problem was only observed when running on top of a buggy emulator.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2021-47560. The exploitation appears 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 05/24/2024).

Upgrading to version 5.10.83 or 5.15.6 eliminates this vulnerability. Applying the patch 90d0736876c5/da4d70199e5d/63b08b1f6834 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.

Entries connected to this vulnerability are available at VDB-269093, VDB-269094, VDB-269095 and VDB-269096.

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: 5.7
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.7
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
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: 90d0736876c5/da4d70199e5d/63b08b1f6834

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-2021-47560 (🔒)
See also: 🔒

Entryinfo

Created: 05/24/2024 06:45 PM
Changes: 05/24/2024 06:45 PM (56)
Complete: 🔍
Cache ID: 34:9BF:40

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