CVE-2021-21311

HIGHNVD 7.29.0▲
EchelonGraph scoreHIGH confidence

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2025-09-29), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 7.2 retained for reference. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: cisa_kev, epss, nvd
Trending — 4 sources updated this weekExploited in the wild
7.2
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV)
CISA-KEV: ExploitedEPSS: 90%CVSS: 7.2Exploit: NoneExposed: 0

A fix is available — apply it.

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 v3
7.2
EG Score
9.0(high)
EG Risk
96(Attend)
EG Risk 96/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity90% × 45%
Exploitation100% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS
99.8%
KEV
⚠ Exploited

Published

February 11, 2021

Last Modified

October 24, 2025

Advisory Details (4)

Auto-updated Jun 11, 2026
Patch available. Sources: github_commit, github.
generic

vrana/adminer - Packagist.org

https://packagist.org/packages/vrana/adminer
generic Patch Available

[SECURITY] [DLA 2580-1] adminer security update

https://lists.debian.org/debian-lts-announce/2021/03/msg00002.html
github Patch Available

SSRF on error page of Elasticsearch and ClickHouse · Advisory · vrana/adminer · GitHub

https://github.com/vrana/adminer/security/advisories/GHSA-x5r2-hj5c-8jx6
github_commit

commit ccd2374b0b12 (vrana/adminer)

Fix landed in vrana/adminer commit ccd2374b0b12 — awaiting tagged release

https://github.com/vrana/adminer/commit/ccd2374b0b12bd547417bf0dacdf153826c83351

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuadminer (4.2.1-1ubuntu1+esm1) @ xenial2026-07-20ubuntu

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
Packagist(1)
PackageVulnerable rangeFixed inDependents
vrana/adminerv4.2.0 ... v4.7.8 (23 versions)4.7.9—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 29× in last 7d / 142× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 267 total refreshes for this CVE.

  1. 2026-07-23 01:57 UTCEG score recompute
  2. 2026-07-22 22:43 UTCEG score recompute
  3. 2026-07-22 19:40 UTCCISA KEV update
  4. 2026-07-22 16:58 UTCEG score recompute
  5. 2026-07-22 14:05 UTCEPSS rescore
  6. 2026-07-21 14:37 UTCCISA KEV update
  7. 2026-07-20 22:33 UTCVendor advisory
  8. 2026-07-20 18:22 UTCEG score recompute
  9. 2026-07-20 17:04 UTCEPSS rescore
  10. 2026-07-20 14:09 UTCVendor advisory
  11. 2026-07-20 09:58 UTCVendor advisory
  12. 2026-07-20 05:46 UTCVendor advisory
  13. 2026-07-20 01:35 UTCVendor advisory
  14. 2026-07-19 21:23 UTCVendor advisory
  15. 2026-07-19 17:11 UTCVendor advisory
  16. 2026-07-19 12:59 UTCVendor advisory
  17. 2026-07-19 08:48 UTCVendor advisory
  18. 2026-07-19 00:24 UTCVendor advisory
  19. 2026-07-18 20:13 UTCVendor advisory
  20. 2026-07-18 16:02 UTCVendor advisory
  21. 2026-07-18 11:49 UTCVendor advisory
  22. 2026-07-18 07:38 UTCVendor advisory
  23. 2026-07-18 03:26 UTCVendor advisory
  24. 2026-07-17 23:15 UTCVendor advisory
  25. 2026-07-17 19:02 UTCVendor advisory
Show 75 more
  1. 2026-07-17 10:38 UTCEG score recompute
  2. 2026-07-16 17:50 UTCVendor advisory
  3. 2026-07-16 17:04 UTCCISA KEV update
  4. 2026-07-16 09:27 UTCVendor advisory
  5. 2026-07-16 05:15 UTCVendor advisory
  6. 2026-07-16 01:03 UTCVendor advisory
  7. 2026-07-15 20:51 UTCVendor advisory
  8. 2026-07-15 16:55 UTCEPSS rescore
  9. 2026-07-15 16:55 UTCEPSS rescore
  10. 2026-07-15 16:49 UTCCISA KEV update
  11. 2026-07-15 15:04 UTCCISA KEV update
  12. 2026-07-15 04:02 UTCVendor advisory
  13. 2026-07-14 23:49 UTCVendor advisory
  14. 2026-07-14 19:37 UTCVendor advisory
  15. 2026-07-14 18:05 UTCCISA KEV update
  16. 2026-07-13 22:39 UTCVendor advisory
  17. 2026-07-13 18:27 UTCVendor advisory
  18. 2026-07-13 17:07 UTCCISA KEV update
  19. 2026-07-13 10:03 UTCVendor advisory
  20. 2026-07-13 05:51 UTCVendor advisory
  21. 2026-07-12 21:27 UTCVendor advisory
  22. 2026-07-12 17:15 UTCVendor advisory
  23. 2026-07-12 13:04 UTCVendor advisory
  24. 2026-07-12 08:52 UTCVendor advisory
  25. 2026-07-12 04:40 UTCVendor advisory
  26. 2026-07-12 00:28 UTCVendor advisory
  27. 2026-07-11 20:16 UTCVendor advisory
  28. 2026-07-11 16:05 UTCVendor advisory
  29. 2026-07-11 11:53 UTCVendor advisory
  30. 2026-07-11 07:40 UTCVendor advisory
  31. 2026-07-11 03:29 UTCVendor advisory
  32. 2026-07-10 23:17 UTCVendor advisory
  33. 2026-07-10 19:06 UTCVendor advisory
  34. 2026-07-10 17:52 UTCCISA KEV update
  35. 2026-07-10 14:54 UTCVendor advisory
  36. 2026-07-10 02:19 UTCVendor advisory
  37. 2026-07-09 22:07 UTCVendor advisory
  38. 2026-07-09 19:07 UTCEPSS rescore
  39. 2026-07-08 20:54 UTCVendor advisory
  40. 2026-07-08 15:12 UTCEPSS rescore
  41. 2026-07-08 08:20 UTCVendor advisory
  42. 2026-07-07 23:53 UTCVendor advisory
  43. 2026-07-07 19:42 UTCVendor advisory
  44. 2026-07-07 19:01 UTCCISA KEV update
  45. 2026-07-07 17:16 UTCCISA KEV update
  46. 2026-07-07 11:18 UTCVendor advisory
  47. 2026-07-07 02:52 UTCVendor advisory
  48. 2026-07-06 22:40 UTCVendor advisory
  49. 2026-07-06 14:16 UTCVendor advisory
  50. 2026-07-06 01:37 UTCVendor advisory
  51. 2026-07-05 21:25 UTCVendor advisory
  52. 2026-07-05 17:13 UTCVendor advisory
  53. 2026-07-05 13:01 UTCVendor advisory
  54. 2026-07-05 08:49 UTCVendor advisory
  55. 2026-07-04 20:09 UTCVendor advisory
  56. 2026-07-04 15:58 UTCVendor advisory
  57. 2026-07-04 07:33 UTCVendor advisory
  58. 2026-07-04 03:20 UTCVendor advisory
  59. 2026-07-03 18:54 UTCVendor advisory
  60. 2026-07-03 14:42 UTCVendor advisory
  61. 2026-07-03 06:16 UTCVendor advisory
  62. 2026-07-03 02:02 UTCVendor advisory
  63. 2026-07-02 21:50 UTCVendor advisory
  64. 2026-07-02 17:38 UTCVendor advisory
  65. 2026-07-02 13:26 UTCVendor advisory
  66. 2026-07-02 09:14 UTCVendor advisory
  67. 2026-07-02 05:02 UTCVendor advisory
  68. 2026-07-02 00:51 UTCVendor advisory
  69. 2026-07-01 20:39 UTCVendor advisory
  70. 2026-07-01 19:16 UTCCISA KEV update
  71. 2026-07-01 16:27 UTCVendor advisory
  72. 2026-07-01 15:03 UTCEPSS rescore
  73. 2026-07-01 12:16 UTCVendor advisory
  74. 2026-07-01 08:05 UTCVendor advisory
  75. 2026-07-01 03:53 UTCVendor advisory

Publicly available exploits

(2 references)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoComoknooni/CVE-2021-21311
    First seen Jun 12, 2023
    Open source ↗
  • Nucleihttp/cves/2021/CVE-2021-21311.yaml
    First seen Jan 1, 2021

    Adminer <4.7.9 - Server-Side Request Forgery

    Open source ↗

Frequently asked(6)

What is CVE-2021-21311?
CVE-2021-21311 is a high vulnerability published on February 11, 2021. 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.
When was CVE-2021-21311 disclosed?
CVE-2021-21311 was first published in the National Vulnerability Database on February 11, 2021, with the most recent update on October 24, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-21311 actively exploited?
Yes. CISA added CVE-2021-21311 to the Known Exploited Vulnerabilities catalog on September 29, 2025, affecting Adminer Adminer. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.
What is the CVSS score of CVE-2021-21311?
CVE-2021-21311 has a CVSS v3 base score of 7.2 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.
Which products are affected by CVE-2021-21311?
CVE-2021-21311 affects Adminer Adminer. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.
How do I remediate CVE-2021-21311?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-21311, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-21311

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