CVE-2025-55210VulnerabilityPublished 12 Feb 2026Updated 26 Feb 2026

CVE-2025-55210: FreePBX api · Privilege Context Switching Error

Affects FreePBX apiSource CVE Database V5

Not known to be exploited · CVSS 2.0 Low : upgrade to 17.0.5 or 16.0.17 when convenient.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 4.0 base score

2.0Low

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 27% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 17.0.5, 16.0.17

CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

Attack Vector: Network
Attack Complexity: High
Attack Requirements: Present
Privileges Required: Low
User Interaction: Active
Vulnerable system confidentiality: Low
Vulnerable system integrity: Low
Vulnerable system availability: None
Subsequent system confidentiality: Low
Subsequent system integrity: Low
Subsequent system availability: None

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

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, 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: High: The successful attack depends on the evasion or circumvention of security-enhancing techniques in place that would otherwise hinder the attack. These include: Evasion of exploit mitigation techniques, for example, circumvention of address space randomization (ASLR) or data execution prevention (DEP) must be performed for the attack to be successful; Obtaining target-specific secrets. The attacker must gather some target-specific secret before the attack can be successful. A secret is any piece of information that cannot be obtained through any amount of reconnaissance. To obtain the secret the attacker must perform additional attacks or break otherwise secure measures (e.g. knowledge of a secret key may be needed to break a crypto channel). This operation must be performed for each attacked target.
Attack Requirements: Present: The successful attack depends on the presence of specific deployment and execution conditions of the vulnerable system that enable the attack. These include: a race condition must be won to successfully exploit the vulnerability (the successfulness of the attack is conditioned on execution conditions that are not under full control of the attacker, or the attack may need to be launched multiple times against a single target before being successful); the attacker must inject themselves into the logical network path between the target and the resource requested by the victim (e.g. vulnerabilities requiring an on-path attacker).
Privileges Required: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: Active: Successful exploitation of this vulnerability requires a targeted user to perform specific, conscious interactions with the vulnerable system and the attacker’s payload, or the user’s interactions would actively subvert protection mechanisms which would lead to exploitation of the vulnerability.
Vulnerable system 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 Vulnerable System.
Vulnerable system 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 to the Vulnerable System.
Vulnerable system availability: None: There is no impact to availability within the Vulnerable System.
Subsequent system 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 Subsequent System.
Subsequent system 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 to the Subsequent System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 12 Feb 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 2026-10-26.

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 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

Upgrade FreePBX api to 17.0.5 or 16.0.17.

Affected software

Product	Affected	Fixed in
FreePBXapi	Affected >=15.0.1alpha1 <16.0.17 >=17.0.0 <17.0.5	Fixed in 17.0.5 16.0.17

AI-suggested

Organizations should immediately upgrade FreePBX installations to versions 17.0.5 or 16.0.17 or later to apply the official fix. In addition, restrict access to the FreePBX API by implementing strong network segmentation and firewall rules to limit API access only to trusted hosts and users. Rotate and securely store the api-oauth.key private key to prevent unauthorized token generation. Audit and monitor API access logs for unusual token usage or privilege escalation attempts. Implement strict database access controls to protect the api_access_tokens table and prevent leakage of valid jti values. Employ multi-factor authentication for API users to reduce the risk of credential compromise. Regularly review and minimize API scopes granted to users to follow the principle of least privilege. Finally, conduct penetration testing and vulnerability assessments focused on FreePBX API security to identify and remediate any residual weaknesses.

Description

FreePBX is an open-source web-based graphical user interface (GUI) that manages Asterisk. Prior to 17.0.5 and 16.0.17, FreePBX module api (PBX API) is vulnerable to privilege escalation by authenticated users with REST/GraphQL API access. This vulnerability allows an attacker to forge a valid JWT with full access to the REST and GraphQL APIs on a FreePBX that they've already connected to, possibly as a lower privileged user. The JWT is signed using the api-oauth.key private key. An attacker can generate their own token if they possess this key (e.g., by accessing an affected instance), and specify any scopes they wish (e.g., rest, gql), bypassing traditional authorization checks. However, FreePBX enforces that the jti (JWT ID) claim must exist in the database (api_access_tokens table in the asterisk MySQL database) in order for the token to be accepted. Therefore, the attacker must know a jti value that already exists on the target instance. This vulnerability is fixed in 17.0.5 and 16.0.17.

Impact

The vulnerability enables authenticated users with limited API access to escalate privileges and gain full control over FreePBX's REST and GraphQL APIs. This can lead to unauthorized configuration changes, exposure of sensitive telephony data, and potential disruption of PBX services. Organizations relying on FreePBX for telephony infrastructure risk compromise of call routing, voicemail, and other critical communications functions. Although exploitation requires some prior access and knowledge, successful attacks could undermine the confidentiality and integrity of telephony systems, impacting business operations and privacy. The limited ease of exploitation and requirement for valid JWT IDs reduce widespread risk, but targeted attacks against organizations with exposed or poorly secured FreePBX instances remain a concern. No known exploits in the wild currently limit immediate widespread impact, but unpatched systems remain vulnerable.

Summary

FreePBX, an open-source web GUI managing Asterisk PBX systems, contains a privilege escalation vulnerability (CVE-2025-55210) in its API module prior to versions 17.0.5 and 16.0.17. The vulnerability stems from a privilege context switching error (CWE-270) that allows authenticated users with REST or GraphQL API access to forge JSON Web Tokens (JWTs) signed with the api-oauth.key private key. Possession of this private key enables attackers to create tokens with arbitrary scopes, such as full REST and GraphQL API access, effectively bypassing normal authorization controls. However, FreePBX enforces that the JWT ID (jti) claim must correspond to an existing token entry in the api_access_tokens table within the Asterisk MySQL database, requiring attackers to know a valid jti value on the target system. This constraint reduces the ease of exploitation, as attackers must have prior access or knowledge of valid token identifiers. The vulnerability allows privilege escalation from lower-privileged authenticated users to full API access, potentially enabling unauthorized configuration changes or information disclosure. No public exploits have been reported to date. The issue is resolved in FreePBX versions 17.0.5 and 16.0.17 by correcting the privilege context handling and token validation mechanisms. The CVSS 4.0 vector indicates network attack vector, high attack complexity, partial authentication, and limited confidentiality and integrity impact, resulting in a low severity rating.

CWE-270Privilege Context Switching Error (opens in a new tab)
Base weakness
The product does not properly manage privileges while it is switching between different contexts that have different privileges or spheres of control.
Architecture and Design · Operation
Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
Architecture and Design · Operation · Environment Hardening
Run your code using the lowest privileges that are required to accomplish the necessary tasks. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment.
Architecture and Design · Separation of Privilege
Consider following the principle of separation of privilege. Require multiple conditions to be met before permitting access to a system resource.
OWASP Cheat Sheets
Docker Security (opens in a new tab)
Third Party Javascript Management (opens in a new tab)
Virtual Patching (opens in a new tab)
OWASP ASVS 4.0.3
V1.4.4 (opens in a new tab)
V1.4.5 (opens in a new tab)
V1.10.1 (opens in a new tab)
Attack patterns
Using Malicious Files (opens in a new tab)
Hijacking a Privileged Thread of Execution (opens in a new tab)
Leverage Executable Code in Non-Executable Files (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 27 Feb 2026, 08:21 UTC

WeaknessesCWE-270

Technical details

References

Community reviews

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