CVE-2021-3964

mediumpriority · track · 24EPSS 0.008 · 57 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.80% (57th) EPSS

CVSS 4.3 · medium

Is it mine?

3 products

Who says so?

4 sources

cnnvd · enisa_euvd · nvd · osv

EPSS · scored 2026-10-27

elgg is vulnerable to Authorization Bypass Through User-Controlled Key

cvss

Technical severity, 0–10. One row per scoring source.

5.9

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 2.2 · impact 3.6

v3.04.3mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nsecondary · ENISA EU

v3.04.3mediumCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nsecondary · security@huntr.devexploitability 2.8 · impact 1.4

v3.15.9mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · OSV

v3.15.4mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

The CWE weakness classes this flaw belongs to.

Products and version ranges known to be affected.

Vendor and ecosystem advisories describing this.

GHSA-gwpx-q2h9-wxgxelgg is vulnerable to Authorization Bypass Through User-Controlled Key2021-12-03ghsa · osvUS
elgg is vulnerable to Authorization Bypass Through User-Controlled Key

Other names and identifiers for this entity.

Which sources assert this record, and when.

published 2021-12-01modified 2026-06-17

External citations — patches, advisories, analysis.

scry

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