IDORSSRFAUTH BYPASSJWT FORGERYRACE CONDITIONXXEBROKEN OBJECT-LEVEL AUTHPRIVILEGE ESCALATIONMASS ASSIGNMENTGRAPHQL INTROSPECTION ABUSEIDORSSRFAUTH BYPASSJWT FORGERYRACE CONDITIONXXEBROKEN OBJECT-LEVEL AUTHPRIVILEGE ESCALATIONMASS ASSIGNMENTGRAPHQL INTROSPECTION ABUSE
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CVE-2021-21311 CISA KEV — actively exploited

Adminer Server-Side Request Forgery Vulnerability

vrana — adminer

Adminer is an open-source database management in a single PHP file. In adminer from version 4.0.0 and before 4.7.9 there is a server-side request forgery vulnerability. Users of Adminer versions bundling all drivers (e.g. `adminer.php`) are affected. This is fixed in version 4.7.9.

CVSS scoreHigh

7.2

EPSS — exploitation probabilityCritical

90.1%

Vector breakdown

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

Published
Feb 11, 2021
Modified
Oct 21, 2025
Added to KEV
Sep 29, 2025
Federal patch due
Oct 20, 2025

CISA required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Weakness classification

CWE-918Server-Side Request Forgery

Proof-of-concept & exploitation references

Weaponization

Nuclei template

Available

Metasploit module

Not found

Public repositories whose name or description references CVE-2021-21311, found via a live GitHub search at request time. These are community-sourced signals, not a verified working exploit - cross-check each one before relying on it, and treat higher star counts and recent activity as (weak) corroboration, not proof.

No public GitHub repositories referencing CVE-2021-21311 were found at last check. Absence here is not proof no exploit exists - see the references below for vendor advisories and write-ups.

References

  • github.com
  • github.com
  • packagist.org
  • github.com
  • lists.debian.org

Frequently asked questions

What is CVE-2021-21311?

Adminer is an open-source database management in a single PHP file. In adminer from version 4.0.0 and before 4.7.9 there is a server-side request forgery vulnerability. Users of Adminer versions bundling all drivers (e.g. `adminer.php`) are affected. This is fixed in version 4.7.9.

How severe is CVE-2021-21311?

CVE-2021-21311 has a CVSS base score of 7.2 out of 10 (CVSS 3.1).

Is CVE-2021-21311 actively exploited in the wild?

Yes. CVE-2021-21311 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added Sep 29, 2025, meaning CISA has confirmed evidence of active exploitation.

What is the EPSS score for CVE-2021-21311?

90.1% - meaning FIRST.org's EPSS model estimates a 90.1% probability this vulnerability will be exploited in the wild within 30 days (100% percentile among all scored CVEs).

Is there exploit tooling available for CVE-2021-21311?

Yes - a public Nuclei template referencing CVE-2021-21311 exist in public repositories we checked.

What type of vulnerability is CVE-2021-21311?

CVE-2021-21311 is classified under CWE-918 (CWE-918: Server-Side Request Forgery (SSRF)).

Cross-checked against

  • NVD (NIST)
  • MITRE CVE Record
  • CISA KEV
  • FIRST.org EPSS
  • GitHub Advisory Database
  • GitHub public repository search

Impactr finds and proves whether CVE-2021-21311 - or flaws like it - are actually reachable in your own web apps and APIs, with a reproducible exploit as evidence.

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