CVE-2021-21311
Confirmed PUBLISHEDSSRF in adminer
1 day faster than CISA KEV
Recommended Action
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
At a Glance
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.
- CVE Published
- Feb 11, 2021
- Exploitation Reported
- Jun 01, 2026
- CVSS
- 7.2 High
- EPSS
- 90.5%
Affected Versions
| Vendor | Product | Version | Status |
|---|---|---|---|
| vrana |
adminer
|
>= 4.0.0, < 4.7.9 |
Affected |
CVE References
- [debian-lts-announce] 20210302 [SECURITY] [DLA 2580-1] adminer security update lists.debian.org · Mailing List https://lists.debian.org/debian-lts-announce/2021/03/msg00002.html
- GitHub — vrana/adminer github.com · CVE Record https://github.com/vrana/adminer/security/advisories/GHSA-x5r2-hj5c-8jx6
- GitHub — vrana/adminer github.com · CVE Record https://github.com/vrana/adminer/files/5957311/Adminer.SSRF.pdf
- packagist.org/packages/vrana/adminer packagist.org · CVE Record https://packagist.org/packages/vrana/adminer
- GitHub — vrana/adminer github.com · CVE Record https://github.com/vrana/adminer/commit/ccd2374b0b12bd547417bf0dacdf1...
Recommended Actions
- Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
- Check enrichment artifacts for scanner coverage and available PoCs before rolling remediation validation.
- Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.
Known Exploited Vulnerability Sources
Catalogues that list this CVE as a known exploited vulnerability.
Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CVE First | 2026-06-01 10:41 UTC |
| CISA | 2026-06-02 14:06 UTC |
Scanner Artifacts
Nuclei and Metasploit references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-21311.yaml | Apr 25, 2025 |
Virtual Patch
Compensating WAF rules to help reduce exposure to this CVE. Rule content and deployable vendor exports are available with KEVIntel Enterprise.
KEVIntel does not currently have a virtual patch for this CVE. When available, KEVIntel virtual patches ship as deployable ModSecurity, Cloudflare, and AWS WAF rules.
Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to KEVIntel Enterprise users.
CVSS Scores
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
AV:N/AC:L/Au:N/C:P/I:P/A:N
Exploitation Status
Exploited in the wild
Recorded 2026-06-01 13:30:37 UTC · CISA
Proof of concept available
Recorded 2022-02-14 18:54:53 UTC · GitHub
Weaknesses (CWE)
-
Server-Side Request Forgery (SSRF)
Scanner Integrations
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-21311.yaml | Apr 25, 2025 |
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
github · Created 2023-06-12 13:32:52 UTC · 2 stars
github · Created 2022-02-14 18:54:53 UTC · 6 stars
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.
nuclei · Created Unknown
Timeline
Key exploitation, disclosure, scanner coverage, and KEV attestation events for this CVE.
-
14:06 UTC about 2 months ago14:06 UTC · about 2 months ago
Added to CISA KEV
Listed in the CISA Known Exploited Vulnerabilities catalog
-
10:41 UTC about 2 months ago10:41 UTC · about 2 months ago
Added to KEVIntel KEV Feed
High-confidence, third-party attested exploitation
-
00:00 UTC about 1 year ago00:00 UTC · about 1 year ago
Nuclei template available
Scanner coverage available
-
18:54 UTC over 4 years ago18:54 UTC · over 4 years ago
Public PoC available
Public proof-of-concept code published
-
20:55 UTC over 5 years ago20:55 UTC · over 5 years ago
CVE published
Vulnerability disclosed publicly
-
00:00 UTC over 5 years ago00:00 UTC · over 5 years ago
CVE ID reserved
Identifier reserved by the CNA
Automate This Intelligence with the Pro API
Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
Pro API Example
GET /api/v2/pro/kevs/CVE-2021-21311
{
"cve_id": "CVE-2021-21311",
"title": "SSRF in adminer",
"affected_vendor": "vrana",
"affected_product": "adminer",
"affected_versions": [
{ "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
],
"confidence": "Confirmed",
"cvss_score": 7.2,
"epss_score": 0.90461,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "...": "Pro API fields" },
"proof_of_concepts": [ "..." ],
"scanner_integrations": [ "..." ]
}