Adminer Server-Side Request Forgery Vulnerability

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

cat cve-2021-21311.json

Vendor: Adminer
Product: Adminer
CVSS: 7.2
EPSS (exploit probability): 98.5%
Status: kev
CISA patch-by (BOD 22-01): October 20, 2025
Added to KEV: September 29, 2025
Source: https://nvd.nist.gov/vuln/detail/CVE-2021-21311

Is CVE-2021-21311 being exploited?

Yes. CISA added CVE-2021-21311 to its Known Exploited Vulnerabilities catalog on September 29, 2025. CISA only lists a CVE when it has reliable evidence of exploitation in the wild.

FIRST's EPSS model puts the probability of exploitation activity in the next 30 days at 98.5% (scored October 14, 2026).

CISA KEV[ LISTED ]
ENISA EUVD (exploited)[ — ]
CIRCL KEV[ — ]

Catalog snapshot 2026-10-23. Full cross-catalog view: /kev-comparison

CVE-2021-21311 timeline

2021-02-11Published to NVD
2025-09-29Added to CISA KEV+1691d

Every event links to its source. Catalog dates are each catalog's own; day offsets count from NVD publication. Data: JSON

What to do

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

US federal civilian agencies must remediate by October 20, 2025 (21 days after listing) under BOD 22-01. Everyone else: that deadline is a sensible upper bound, not a target. Vendor guidance and the NVD record are linked under Source above.