VulnerabilityPublished 26 Feb 2024Updated 30 May 2025

CVE-2024-24721: Improper Restriction of Excessive Authentication Attempts

Source CVE Database V5

Not known to be exploited · CVSS 6.5 Medium.

Data as of 26 Oct 2026, 11:07 UTC

CVSS 3.1 base score

6.5Medium

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 23% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: Low
Integrity: Low
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: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on 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 26 Feb 2024
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.

What to do

AI-suggested

To mitigate this vulnerability effectively, European organizations should: 1) Upgrade Innovaphone PBX devices to version 14r1 or later as soon as the vendor releases a patch or updated firmware addressing this issue. 2) Implement network-level protections such as firewall rules to restrict access to the PBX administration interface to trusted IP addresses or internal networks only. 3) Deploy intrusion detection or prevention systems (IDS/IPS) capable of detecting and blocking brute force attempts against the PBX authentication portal. 4) Enforce strong password policies for administrative accounts, including complexity and regular rotation, to reduce the risk of successful brute force attacks. 5) If possible, enable multi-factor authentication (MFA) for administrative access to add an additional layer of security beyond passwords. 6) Monitor PBX logs for repeated failed login attempts and configure alerts to respond promptly to suspicious activity. 7) Consider segmenting the PBX management network away from general user networks to limit exposure. These measures, combined with timely patching, will significantly reduce the risk posed by this vulnerability.

Description

An issue was discovered on Innovaphone PBX before 14r1 devices. The password form, used to authenticate, allows a Brute Force Attack through which an attacker may be able to access the administration panel

Impact

For European organizations, the impact of this vulnerability can be significant, especially for enterprises, government agencies, and service providers relying on Innovaphone PBX systems for critical voice communications. Unauthorized administrative access could lead to interception of sensitive calls, manipulation of call routing, or disruption of telephony services, potentially affecting business operations and confidentiality of communications. Given the reliance on PBX systems for internal and external communications, exploitation could facilitate espionage, fraud, or denial of telephony services. The medium severity score suggests that while the vulnerability does not directly cause service outages, the confidentiality and integrity risks are notable. Organizations in sectors such as finance, healthcare, and public administration, which handle sensitive information, may face increased risks. Additionally, the network-based attack vector means that attackers can attempt exploitation remotely, increasing the threat surface. The absence of known exploits currently provides a window for proactive defense, but the ease of exploitation due to lack of authentication or user interaction requirements means that attackers could develop exploits rapidly if motivated.

CWE-307Improper Restriction of Excessive Authentication Attempts (opens in a new tab)
Base weaknessOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame.
Architecture and Design
Common protection mechanisms include: Disconnecting the user after a small number of failed attempts; Implementing a timeout; Locking out a targeted account; Requiring a computational task on the user's part.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
OWASP Cheat Sheets
Authentication (opens in a new tab)
Transport Layer Protection (opens in a new tab)
TLS Cipher String (opens in a new tab)
OWASP ASVS 4.0.3
V2.2.1 (opens in a new tab)
V2.8.5 (opens in a new tab)
V2.8.4 (opens in a new tab)
Attack patterns
Dictionary-based Password Attack (opens in a new tab)
Password Brute Forcing (opens in a new tab)
Password Spraying (opens in a new tab)
Credential Stuffing (opens in a new tab)
Use of Known Kerberos Credentials (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

Description

AI analysisMachine-generated, updated 8 Jul 2025, 16:10 UTC

WeaknessesCWE-307

Technical details

References

Community reviews

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