// For flags

CVE-2021-20177

Debian Security Advisory 4843-1

Severity Score

4.4
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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.

Se encontró un fallo en la implementación del kernel de Linux de la coincidencia de cadenas dentro de un paquete. Un usuario privilegiado (con root o función CAP_NET_ADMIN) cuando se insertan las reglas de iptables podría insertar una regla que puede causar pánico en el sistema. El kernel anterior al kernel 5.5-rc1 está afectado

Bodong Zhao discovered a use-after-free in the Sun keyboard driver implementation in the Linux kernel. A local attacker could use this to cause a denial of service or possibly execute arbitrary code. It was discovered that the jfs file system implementation in the Linux kernel contained an out-of-bounds read vulnerability. A local attacker could use this to possibly cause a denial of service. Various other issues were also addressed.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
High
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Local
Attack Complexity
Low
Authentication
None
Confidentiality
None
Integrity
None
Availability
Partial
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2020-12-17 CVE Reserved
  • 2021-02-25 CVE Published
  • 2024-08-03 CVE Updated
  • 2025-03-19 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-125: Out-of-bounds Read
CAPEC
References (1)
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
<= 5.4.9
Search vendor "Linux" for product "Linux Kernel" and version " <= 5.4.9"
-
Affected