CVEs / CVE-2021-21311
CVE-2021-21311: Adminer Server-Side Request Forgery Vulnerability
- Known exploited in the CISA KEV catalog since 29 Sep 2025
- high 7.2 CVSS 3.1 (NVD)
- EPSS 98.4% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Adminer contains a server-side request forgery vulnerability that, when exploited, allows a remote attacker to obtain potentially sensitive information.
Description
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.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| vrana adminer | >= 4.0.0, < 4.7.9 | — |
| Product | Affected | Fixed in |
|---|---|---|
| vrana/adminer (Packagist) | before 4.7.9 | 4.7.9 |
Package versions from GHSA-x5r2-hj5c-8jx6.
Exploitation
| In CISA KEV since | 29 Sep 2025 |
|---|---|
| Due date for US federal agencies | 20 Oct 2025 |
| Used in ransomware campaigns | Unknown |
| 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. |
Severity
| CVSS 3.1 | 7.2 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:NScored by NVD |
|---|---|
| Weakness | CWE-918 |
References
- CVE-2021-21311 on NVD
- CVE-2021-21311 in the CISA KEV catalog
- https://github.com/vrana/adminer/security/advisories/GHSA-x5r2-hj5c-8jx6 (cited by CISA)
- CVE-2021-21311 on OSV
- https://github.com/vrana/adminer/commit/ccd2374b0b12bd547417bf0dacdf153826c83351 Patch
- https://github.com/vrana/adminer/files/5957311/Adminer.SSRF.pdf Exploit, Third Party Advisory
- https://github.com/vrana/adminer/security/advisories/GHSA-x5r2-hj5c-8jx6 Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/03/msg00002.html Mailing List, Third Party Advisory
- https://packagist.org/packages/vrana/adminer Product, Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-21311 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.