CVE-2021-21311

criticalknown exploitedpublic exploitcovered by 1 sourcefirst seen 2025-09-29

Actively exploited. CVE-2021-21311 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-09-29) — exploitation has been observed in the wild, and US federal agencies are required to remediate it under BOD 22-01. Treat patching as urgent.

Public exploit code is available. Proof-of-concept or working exploit code for CVE-2021-21311 is indexed in GitHub PoC and Nuclei. Expect opportunistic scanning and exploitation attempts — prioritize remediation.

Adminer contains a server-side request forgery vulnerability that, when exploited, allows a remote attacker to obtain potentially sensitive information.

CSIRTS triage

What: The vulnerability allows remote attackers to obtain potentially sensitive information via server-side request forgery.
Who is affected: Users of Adminer applications.
Urgency: Immediate action is required due to active exploitation and critical severity.
Action: Update Adminer to the latest version.

AI-assisted analysis generated from the source advisory — verify against the original.

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Exploitation outlook

Exploitation confirmedAlready exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 100% of all EPSS-scored CVEs.

Exploit availability

Public exploit or proof-of-concept code for CVE-2021-21311 is indexed in these free datasets. Available exploit code raises real-world risk independent of the CVSS score.

GitHub PoCPublic proof-of-concept repositories on GitHub reference this CVE.look it up ↗
NucleiA nuclei-templates detection/PoC template exists for this CVE.look it up ↗

Advisory coverage (1)

criticalexploitedCVE-2021-21311: Adminer Server-Side Request Forgery Vulnerabilitycisa-kev · 2025-09-29

External references

NVD record for CVE-2021-21311

CVE.org record

CISA KEV catalog

Embed the live status

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