CVE-2021-39189: Observable Response Discrepancy in Lost Password Service

Severity: medium (CVSS 5.0 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-09-15 · updated 2026-06-17
Weakness: CWE-204

Description

Pimcore is an open source data & experience management platform. In versions prior to 10.1.3, it is possible to enumerate usernames via the forgot password functionality. This issue is fixed in version 10.1.3. As a workaround, one may apply the available patch manually.

Affected products

pimcore/pimcore: before 10.1.3 — fixed in 10.1.3

How to fix

Upgrade to a fixed version: pimcore/pimcore 10.1.3. Check the vendor advisory for mitigations.

References

https://github.com/pimcore/pimcore/pull/10223.patch
https://github.com/pimcore/pimcore/pull/10223/commits/d0a4de39cf05dce6af71f8ca039132bdfcbb0dce
https://github.com/pimcore/pimcore/security/advisories/GHSA-579x-cjvr-cqj9
https://huntr.dev/bounties/12462a99-ebf8-4e39-80b3-54a16caa3f4c/
https://github.com/pimcore/pimcore/pull/10223.patch
https://github.com/pimcore/pimcore/pull/10223/commits/d0a4de39cf05dce6af71f8ca039132bdfcbb0dce
https://github.com/pimcore/pimcore/security/advisories/GHSA-579x-cjvr-cqj9
https://huntr.dev/bounties/12462a99-ebf8-4e39-80b3-54a16caa3f4c/

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