CVE-2024-0391VulnerabilityPublished 11 May 2026

The check user account lock states feature within the email OTP flow fails to validate user input, allowing an

Source GCVE Database

Authoritative record:CVE-2024-0391· Medium 5.3

Not known to be exploited · CVSS 5.3 Medium · fixed in 7.0.0.131 : update WSO2 Identity Server when convenient.

Data as of 27 Oct 2026, 01:31 UTC

CVSS 3.1 base score

5.3Medium

How severe the flaw is on the 0–10 CVSS scale.

Patch: Available – fixed in 7.0.0.131, 6.1.0.254, 6.0.0.253 +11

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: Low
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 11 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-r9x2-mg2v-mq96

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
WSO2WSO2 Identity Server	Affected >=7.0.0 <7.0.0.131	Fixed in 7.0.0.131
WSO2WSO2 Identity Server	Affected >=6.1.0 <6.1.0.254	Fixed in 6.1.0.254
WSO2WSO2 Identity Server	Affected >=6.0.0 <6.0.0.253	Fixed in 6.0.0.253
WSO2WSO2 Identity Server	Affected >=5.11.0 <5.11.0.431	Fixed in 5.11.0.431
WSO2WSO2 Identity Server	Affected >=5.11.0 <5.11.0.426	Fixed in 5.11.0.426
WSO2WSO2 Identity Server	Affected >=5.10.0 <5.10.0.379	Fixed in 5.10.0.379

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

In the meantime, consider implementing rate limiting, account lockout policies, or other controls to mitigate user enumeration risks. Avoid revealing explicit user existence information in error messages or responses during authentication flows.

Description

A vulnerability in the email OTP flow's user account lock state check allows attackers to confirm the existence of registered user accounts by bypassing input validation. This information disclosure can facilitate brute-force and social engineering attacks, increasing risks such as targeted phishing and potential regulatory and financial impacts.

Impact

The primary impact is information disclosure through user enumeration, which can aid attackers in identifying valid usernames. This increases the likelihood of successful brute-force attacks and targeted phishing campaigns. While the vulnerability does not directly compromise confidentiality, integrity, or availability, it raises the risk profile for subsequent attacks that could lead to data breaches or regulatory non-compliance.

Summary

The vulnerability (CVE-2024-0391) involves the failure of the 'check user account lock states' feature within the email OTP flow to properly validate user input. This flaw enables attackers to infer whether specific usernames are registered in the system. Such user enumeration can be leveraged to conduct brute-force attacks or craft targeted social engineering campaigns. The CVSS 3.1 base score is 5.3 (medium severity), reflecting the network attack vector, low complexity, no privileges required, and no user interaction needed, with limited confidentiality impact and no integrity or availability impact.

CWE-204Observable Response Discrepancy (opens in a new tab)
Base weakness
The product provides different responses to incoming requests in a way that reveals internal state information to an unauthorized actor outside of the intended control sphere.
Architecture and Design · Separation of Privilege
Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
Implementation
Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended).
OWASP Cheat Sheets
Error Handling (opens in a new tab)
Logging (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.4 (opens in a new tab)
V14.3.3 (opens in a new tab)
V7.3.3 (opens in a new tab)
Attack patterns
ICMP IP Total Length Field Probe (opens in a new tab)
ICMP IP 'ID' Field Error Message Probe (opens in a new tab)
Application Fingerprinting (opens in a new tab)
System Footprinting (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 27 Oct 2026, 01:31 UTC

WeaknessesCWE-204

Technical details

References

Community reviews

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