CVE-2026-81891

HIGHPre-NVD 8.18.1—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5%, top 56% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 8.1Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

elFinder is an open-source file manager for web, written in JavaScript using jQuery UI. Prior to 2.1.70, checkExtractItems() in php/elFinderVolumeDriver.class.php calls mimetypeInternalDetect() without passing the result through mimeTypeNormalize(). Because the .phtml, .phar, .php5, and .php3 extensions are absent from mime.types, the staticMimeMap entries that map them to text/x-php are not applied, and allowPutMime() permits extraction even when uploadDeny blocks text/x-php. An attacker with ZIP upload permission can extract PHP-executable files into a web-accessible files/ directory and achieve remote code execution when the server executes those extensions. This issue is fixed in version 2.1.70.

CVSS v3
8.1
EG Score
8.1(medium)
EG Risk
37(Track)
EG Risk 37/100SSVC: Track

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
Severity81% × 45%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
44%
KEV
Not listed

Published

August 31, 2026

Last Modified

September 9, 2026

Advisory Details (4)

Auto-updated Aug 31, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit, github_release.
github_release Patch Available

Version 2.1.70

Patch available: Studio-42/elFinder 2.1.70

https://github.com/Studio-42/elFinder/releases/tag/2.1.70
github_commit

commit dd73e702820c (Studio-42/elFinder)

Fix landed in Studio-42/elFinder commit dd73e702820c — awaiting tagged release

https://github.com/Studio-42/elFinder/commit/dd73e702820c146a192969800ee674ecdb208365
github_commit Patch Available

commit 191372c1bbeb (Studio-42/elFinder)

Patch available: Studio-42/elFinder 2.1.70 (contains commit 191372c1bbeb)

https://github.com/Studio-42/elFinder/commit/191372c1bbebbd36fb55af79a84b9984861390ff
github Patch Available🟡 PoC Available

ZIP extraction bypasses uploadDeny MIME filter allowing PHP file upload (RCE) · Advisory · Studio-42/elFinder · GitHub

https://github.com/Studio-42/elFinder/security/advisories/GHSA-gxmj-r5rf-ggwq

Vendor Advisories for CVE-2026-81891(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
Packagist(1)
PackageVulnerable rangeFixed inDependents
Studio-42/elFinder—2.1.70—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 13× in last 7d / 37× 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.

  1. 2026-09-21 04:12 UTCEG score recompute
  2. 2026-09-20 20:16 UTCEPSS rescore
  3. 2026-09-19 18:19 UTCEG score recompute
  4. 2026-09-18 19:44 UTCEG score recompute
  5. 2026-09-18 19:28 UTCEPSS rescore
  6. 2026-09-17 21:09 UTCEG score recompute
  7. 2026-09-16 22:35 UTCEG score recompute
  8. 2026-09-16 14:08 UTCEPSS rescore
  9. 2026-09-16 11:16 UTCEG score recompute
  10. 2026-09-16 05:15 UTCEPSS rescore
  11. 2026-09-15 12:41 UTCEG score recompute
  12. 2026-09-15 03:12 UTCEPSS rescore
  13. 2026-09-15 03:12 UTCEPSS rescore
  14. 2026-09-14 02:47 UTCEG score recompute
  15. 2026-09-12 16:56 UTCEG score recompute
  16. 2026-09-11 18:22 UTCEG score recompute
  17. 2026-09-11 14:53 UTCEPSS rescore
  18. 2026-09-11 14:53 UTCEPSS rescore
  19. 2026-09-10 19:47 UTCEG score recompute
  20. 2026-09-08 23:28 UTCEG score recompute
  21. 2026-09-08 22:01 UTCEPSS rescore
  22. 2026-09-07 19:19 UTCEG score recompute
  23. 2026-09-06 20:41 UTCEG score recompute
  24. 2026-09-06 13:48 UTCEPSS rescore
  25. 2026-09-05 22:05 UTCEG score recompute
Show 12 more
  1. 2026-09-05 15:31 UTCEPSS rescore
  2. 2026-09-04 23:28 UTCEG score recompute
  3. 2026-09-04 11:42 UTCEG score recompute
  4. 2026-09-04 05:07 UTCEPSS rescore
  5. 2026-09-02 14:16 UTCEG score recompute
  6. 2026-09-02 14:12 UTCEPSS rescore
  7. 2026-09-01 15:42 UTCEG score recompute
  8. 2026-09-01 15:13 UTCEG score recompute
  9. 2026-09-01 13:54 UTCEPSS rescore
  10. 2026-08-31 21:21 UTCEG score recompute
  11. 2026-08-31 20:40 UTCEG score recompute
  12. 2026-08-31 20:39 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-81891?
CVE-2026-81891 is a high vulnerability published on August 31, 2026. elFinder is an open-source file manager for web, written in JavaScript using jQuery UI. Prior to 2.1.70, checkExtractItems() in php/elFinderVolumeDriver.class.php calls mimetypeInternalDetect() without passing the result through mimeTypeNormalize(). Because the .phtml, .phar, .php5, and .php3…
When was CVE-2026-81891 disclosed?
CVE-2026-81891 was first published in the National Vulnerability Database on August 31, 2026, with the most recent update on September 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-81891 actively exploited?
CVE-2026-81891 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 56.4% of all scored CVEs.
What is the CVSS score of CVE-2026-81891?
CVE-2026-81891 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-81891?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-81891, 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

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