CVE-2020-21468Network attack vector

Remote service crash through undisclosed network interaction

Published Sep 20, 2021 · Updated Jul 9, 2026

A reported denial-of-service flaw in Redis 5.0.7 allows remote attackers to crash redis-server via an unspecified network interaction. The sole upstream report shows je_large_dalloc faulting during clientAcceptHandler but does not identify the input or invalid operation that triggered it. The report concerns an unreleased development build labeled 999.999.999, and the vendor could not reproduce the crash in released 5.0.7.

CVSS severity7.5
High
EPSS probability1.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A reported denial-of-service flaw in Redis 5.0.7 allows remote attackers to crash redis-server via an unspecified network interaction. The sole upstream report shows je_large_dalloc faulting during clientAcceptHandler but does not identify the input or invalid operation that triggered it. The report concerns an unreleased development build labeled 999.999.999, and the vendor could not reproduce the crash in released 5.0.7.

The record

CVE
CVE-2020-21468
Published
Sep 20, 2021
Updated
Jul 9, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 20, 2021CVE publishedPublication date reported by the CVE source.
  2. Jul 9, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

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

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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