CVE-2021-21311Known exploitationPublic exploitNetwork attack vector

Internal HTTP response disclosure via database driver errors

Published Feb 11, 2021 · Updated Oct 21, 2025

Server-side request forgery in Adminer 4.0.0 through 4.7.8 allows remote attackers to read HTTP responses from internal services. The Elasticsearch and ClickHouse drivers copy a non-2xx response body into the login error, returning data fetched from an attacker-supplied server address. The unauthenticated path affects all-drivers builds and exposes reachable HTTP endpoints and cloud metadata responses through the application.

CVSS severity7.2
High
EPSS probability90.46%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Server-side request forgery in Adminer 4.0.0 through 4.7.8 allows remote attackers to read HTTP responses from internal services. The Elasticsearch and ClickHouse drivers copy a non-2xx response body into the login error, returning data fetched from an attacker-supplied server address. The unauthenticated path affects all-drivers builds and exposes reachable HTTP endpoints and cloud metadata responses through the application.

The record

CVE
CVE-2021-21311
Published
Feb 11, 2021
Updated
Oct 21, 2025
Vendor
Adminer
Product
Adminer
Classifications
CWE-918, CAPEC-664, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 11, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2025Record 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=>= 4.0.0, < 4.7.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Adminer · Adminerversion=>= 4.0.0, < 4.7.9

Published CVSS scores

7.2UbuntuCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
7.2GitHubCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N/E: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 exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
CAPEC-664Server Side Request Forgery
T1190Exploit Public-Facing Application

Public exploit references

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

Reported exploitation

Technologies

Your stack

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Your stack

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