VDB-149377 · CVE-2019-20422 · Nessus 249897

Linux Kernel up to 5.3.3 net/ipv6/ip6_fib.c fib6_rule_lookup RT6_LOOKUP_F_DST_NOREF exceptional condition

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4.3	$0-$5k	0.00

Summaryinfo

A vulnerability marked as problematic has been reported in Linux Kernel up to 5.3.3. This affects the function fib6_rule_lookup of the file net/ipv6/ip6_fib.c. This manipulation of the argument RT6_LOOKUP_F_DST_NOREF as part of Flag causes exceptional condition. This vulnerability is tracked as CVE-2019-20422. The attack is restricted to local execution. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 5.3.3 (Operating System) and classified as problematic. Affected by this vulnerability is the function fib6_rule_lookup of the file net/ipv6/ip6_fib.c. The manipulation of the argument RT6_LOOKUP_F_DST_NOREF as part of a Flag leads to a exceptional condition vulnerability. The CWE definition for the vulnerability is CWE-755. The product does not handle or incorrectly handles an exceptional condition. As an impact it is known to affect availability. The summary by CVE is:

In the Linux kernel before 5.3.4, fib6_rule_lookup in net/ipv6/ip6_fib.c mishandles the RT6_LOOKUP_F_DST_NOREF flag in a reference-count decision, leading to (for example) a crash that was identified by syzkaller, aka CID-7b09c2d052db.

The weakness was disclosed 01/27/2020. This vulnerability is known as CVE-2019-20422 since 01/27/2020. The exploitation appears to be easy. An attack has to be approached locally. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 249897 (Linux Distros Unpatched Vulnerability : CVE-2019-20422), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.3.4 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (249897). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Operating System

Vendor

Linux

Name

Kernel

Version

License

open-source

Website

Vendor: https://www.kernel.org/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.3

VulDB Base Score: 3.3
VulDB Temp Score: 3.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Exceptional condition
CWE: CWE-755
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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Nessus ID: 249897
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2019-20422

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Kernel 5.3.4
Patch: github.com

Timelineinfo

01/27/2020 🔍
01/27/2020 +0 days 🔍
01/27/2020 +0 days 🔍
08/18/2025 +2030 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: 7b09c2d052db4b4ad0b27b97918b46a7746966fa
Status: Confirmed

CVE: CVE-2019-20422 (🔍)
GCVE (CVE): GCVE-0-2019-20422
GCVE (VulDB): GCVE-100-149377

Entryinfo

Created: 01/27/2020 08:02
Updated: 08/18/2025 03:16
Changes: 01/27/2020 08:02 (41), 01/27/2020 08:07 (18), 03/26/2024 11:52 (20), 08/18/2025 03:16 (5)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.