CVE-2021-20297

Daemon crash via NULL device-path matching

Published May 26, 2021 · Updated Aug 3, 2024

Improper input validation in Red Hat NetworkManager before 1.30.0 allows local users to crash the daemon by activating a match.path profile. During profile matching, nm_wildcard_match_check() treats an absent device path as a string and dereferences the NULL value. Low-privileged local access is required, and the resulting daemon crash interrupts network management and can disrupt managed connectivity.

CVSS severity5.5
Medium
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Red Hat NetworkManager before 1.30.0 allows local users to crash the daemon by activating a match.path profile. During profile matching, nm_wildcard_match_check() treats an absent device path as a string and dereferences the NULL value. Low-privileged local access is required, and the resulting daemon crash interrupts network management and can disrupt managed connectivity.

The record

CVE
CVE-2021-20297
Published
May 26, 2021
Updated
Aug 3, 2024
Vendor
Red Hat
Product
NetworkManager
Classifications
CWE-20, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 26, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=NetworkManager 1.30.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Red Hat · NetworkManagerversion=NetworkManager 1.30.0

Published CVSS scores

5.5NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
5.5CanonicalCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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