CVE-2024-0391 | Username Enumeration via Email OTP Flow in Multiple WSO2 Products Allows User Account Discovery

The check user account lock states feature within the email OTP flow fails to validate user input, allowing an attacker to infer the existence of registered user accounts. The discovery of valid usernames can increase the risk of brute-force and social engineering attacks. Attackers can leverage this information to craft targeted phishing campaigns or other malicious activities aimed at tricking users into divulging sensitive data, potentially damaging the organization's reputation and leading to regulatory non-compliance and financial consequences.

Published: 2026-05-11 Last update: 2026-05-27 Assigner: ed10eef1-636d-4fbe-9993-6890dfa878f8 Source: ed10eef1-636d-4fbe-9993-6890dfa878f8
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2024-0391 is rated Low Risk (23.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2024-0391

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-11 — 0.02% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-0391

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 ed10eef1-636d-4fbe-9993-6890dfa878f8
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 1.4 [email protected]

Weakness enumeration for CVE-2024-0391

GitHub Security Advisory for CVE-2024-0391

GHSA-r9x2-mg2v-mq96 · Severity: medium — The check user account lock states feature within the email OTP flow fails to validate user input...

Affected software / configurations for CVE-2024-0391

Vendor Product Version Raw CPE
wso2 identity_server >= 5.10.0, < 5.10.0.379 cpe:2.3:a:wso2:identity_server:*:*:*:*:*:*:*:*
wso2 identity_server >= 5.11.0, < 5.11.0.426 cpe:2.3:a:wso2:identity_server:*:*:*:*:*:*:*:*
wso2 identity_server >= 6.0.0, < 6.0.0.253 cpe:2.3:a:wso2:identity_server:*:*:*:*:*:*:*:*
wso2 identity_server >= 6.1.0, < 6.1.0.254 cpe:2.3:a:wso2:identity_server:*:*:*:*:*:*:*:*
wso2 identity_server >= 7.0.0, < 7.0.0.131 cpe:2.3:a:wso2:identity_server:*:*:*:*:*:*:*:*
wso2 identity_server_as_key_manager >= 5.10.0, < 5.10.267 cpe:2.3:a:wso2:identity_server_as_key_manager:*:*:*:*:*:*:*:*
wso2 open_banking_iam >= 2.0.0, < 2.0.0.318 cpe:2.3:a:wso2:open_banking_iam:*:*:*:*:*:*:*:*

References for CVE-2024-0391

cvelogic Threat Intelligence