CVE-2021-3964: elgg is vulnerable to Authorization Bypass Through User-Controlled Key

medium Affects elgg/elgg. Feed 2026.10.29.4, updated 2026-10-29; published 2021-12-03; advisory modified 2024-02-17.

elgg is vulnerable to Authorization Bypass Through User-Controlled Key

Package: elgg/elgg Composer
Affected versions: <3.3.22
Fixed in: 3.3.22
Severity: medium CVSS 5.9
Exploitation: not on CISA KEV · EPSS 1% (56.7th percentile)
Published: 2021-12-03
Source: osv.dev

References

Am I affected?

Find out in one command. phpwarden checks your composer.lock against this advisory and 20,000+ others, ranked by real-world exploitation (CISA KEV + EPSS). Free, offline, open data.

# PHP projects (recommended)
composer require --dev phpwarden/phpwarden
# then
vendor/bin/phpwarden deps composer.lock

# or, without Composer
pipx install phpwarden   &&   phpwarden deps composer.lock

Or keep it checked automatically: GitHub Action · pre-commit hook · GitLab CI · Laravel artisan command

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