CVE-2021-20177
A flaw was found in the Linux kernel's implementation of string matching within a packet.
Does this matter?
Lower severity and a low EPSS score (0.28%). Track it; it rarely justifies an emergency change on its own.
Description
A flaw was found in the Linux kernel's implementation of string matching within a packet. A privileged user (with root or CAP_NET_ADMIN) when inserting iptables rules could insert a rule which can panic the system. Kernel before kernel 5.5-rc1 is affected.
- CVSS 3.1
- 4.4 MEDIUMCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.28% probability · 21th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-125
- Affected
- linux/linux kernel
- Source
- secalert@redhat.com
EPSS 0.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://bugzilla.redhat.com/show_bug.cgi?id=1914719Issue Tracking, Patch, Third Party Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1914719Issue Tracking, Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.