CVE-2021-21510Network attack vector

Web-cache poisoning via unvalidated Host header

Published Mar 8, 2021 · Updated Sep 16, 2024

Host header injection in Dell iDRAC8 before 2.75.100.75 allows remote attackers to poison web caches or trigger redirects. The HTTP interface accepts an arbitrary Host header and uses the unvalidated value when generating cacheable responses or redirect targets. Exploitation requires no account and user interaction; Dell reports cache poisoning and redirection, not service interruption.

CVSS severity6.1
Medium
EPSS probability1.03%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Host header injection in Dell iDRAC8 before 2.75.100.75 allows remote attackers to poison web caches or trigger redirects. The HTTP interface accepts an arbitrary Host header and uses the unvalidated value when generating cacheable responses or redirect targets. Exploitation requires no account and user interaction; Dell reports cache poisoning and redirection, not service interruption.

The record

CVE
CVE-2021-21510
Published
Mar 8, 2021
Updated
Sep 16, 2024
Vendor
Dell Technologies
Product
Integrated Dell Remote Access Controller (iDRAC)
Classifications
CWE-74, CWE-20, T1565.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 8, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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=unspecified <2.75.100.75

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Dell Technologies · Integrated Dell Remote Access Controller (iDRAC)version=unspecified <2.75.100.75

Published CVSS scores

6.1Dell TechnologiesCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
5.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:N
6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

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

CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
CWE-20Improper Input Validation
T1565.001Stored Data Manipulation

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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