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CVE-2021-37151
CyberArk Identity 21.5.131, when handling an invalid authentication attempt, sometimes reveals whether the username is valid. In certain…
Medium5.3EPSS 0.85%
- Published
- Updated
- Reserved
- Assigned by
- INCD
Description
CyberArk Identity 21.5.131, when handling an invalid authentication attempt, sometimes reveals whether the username is valid. In certain authentication policy configurations with MFA, the API response length can be used to differentiate between a valid user and an invalid one (aka Username Enumeration). Response differentiation enables attackers to enumerate usernames of valid application users. Attackers can use this information to leverage brute-force and dictionary attacks in order to discover valid account information such as passwords.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NVDNVD · Modified | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.85% · top 42% of all CVEs (6 Nov 2026)
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The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Weakness
- Username Enumeration Vulnerability
- CWE-203 (opens in a new tab)All about CWE-203 and its CVEs
Affected products
References (2)
- https://www.cyberark.com/products/ (opens in a new tab)x_refsource_MISCx_transferred
- https://www.gov.il/en/departments/faq/cve_advisories (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://trackcve.app/cve/CVE-2021-37151)Record last updated .