CVE-2019-20422

Name: CVE-2019-20422
Creator: NVD / NIST
Published: 2020-01-27T05:15:10.657+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.5/10EPSS 0.43%

Last modified Jun 17, 2026

CVE-2019-20422 is a medium-severity vulnerability rated 5.5/10 on the CVSS scale. 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.. EPSS estimates a 0.43% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

5.5/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.43%

34.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-755

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	< 5.3.4

References

https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.3.4Mailing List, Vendor Advisory
https://github.com/torvalds/linux/commit/7b09c2d052db4b4ad0b27b97918b46a7746966faPatch, Third Party Advisory
https://security.netapp.com/advisory/ntap-20200313-0003/
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.3.4Mailing List, Vendor Advisory
https://github.com/torvalds/linux/commit/7b09c2d052db4b4ad0b27b97918b46a7746966faPatch, Third Party Advisory
https://security.netapp.com/advisory/ntap-20200313-0003/

Timeline

Published: Jan 27, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-20422?

How severe is CVE-2019-20422?

CVE-2019-20422 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.43% probability of exploitation in the next 30 days.

How do I fix CVE-2019-20422?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2019-20422?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST