VulnerabilityModified

CVE-2021-37151

Response differentiation enables attackers to enumerate usernames of valid application users.

MEDIUM 5.3EPSS 0.85%

Does this matter?

Lower severity and a low EPSS score (0.85%). Track it; it rarely justifies an emergency change on its own.

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.

CVSS 3.1: 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
EPSS: 0.85% probability · 56th percentile
CISA KEV: Not listed
Weakness: CWE-203
Affected: cyberark/identity
Source: cna@cyber.gov.il

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.