CVE-2021-22555NVD

Vulnerability Summary

A heap out-of-bounds write affecting Linux since v2.6.19-rc1 was discovered in net/netfilter/x_tables.c. This allows an attacker to gain privileges or cause a DoS (via heap memory corruption) through user name space

Severity Level

HIGH(8.3)

Published Date

Jul 7, 2021

Last Modified

Dec 30, 2025

PoC

Available(Metasploit)

Exploitation Status

ACTIVE

EPSS Score (30-Day)

Data Pending

Root Weakness (CWE)

CWE-787: Unknown/Unlisted Weakness ↗

Refer to the official MITRE database for detailed architectural specifications regarding this weakness.

CVSS v3.1 Base Metrics — Score 8.3 (HIGH)

Attack VectorAdjacent

Attack ComplexityHigh

Privileges RequiredNone

User InteractionNone

ScopeChanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

Affected & Patched Versions

Affected Versions

n/a Linux Kernel >= 2.6.19-rc1 and < unspecified

Patched Versions

n/a Linux Kernel unspecified

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