VulnerabilityPublished 24 Nov 2025

CVE-2025-65502: mongoose · NULL Pointer Dereference

Affects mongooseSource CVE Database V5

Not known to be exploited · CVSS 4.3 Medium : upgrade to 7.2 when convenient.

Data as of 26 Oct 2026, 09:15 UTC

CVSS 3.1 base score

4.3Medium

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

EPSS: 0.3% chance of exploitation in 30 days – higher than 22% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 7.2

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

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

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: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
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: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 24 Nov 2025
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 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 cesanta/mongoose to 7.2.

Affected software

Product	Affected	Fixed in
GitHubcesanta/mongoose`pkg:github/cesanta/mongoose`Other threats	Affected <7.2	Fixed in 7.2

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

AI-suggested

1. Upgrade Cesanta Mongoose to version 7.2 or later once the patch addressing this vulnerability is released. 2. In the interim, implement additional error handling around TLS initialization code to verify that SSL_CTX_get_cert_store() does not return NULL before dereferencing. 3. Employ network-level protections such as rate limiting and firewall rules to restrict access to services using Mongoose, reducing exposure to malicious TLS connection attempts. 4. Monitor logs for abnormal TLS handshake failures or crashes that may indicate exploitation attempts. 5. For embedded or IoT devices, ensure secure firmware update mechanisms are in place to deploy patches promptly. 6. Conduct code audits on custom integrations of Mongoose to identify and remediate similar null pointer dereference risks. 7. Educate developers on secure TLS initialization practices and proper validation of SSL context components.

Description

Null pointer dereference in add_ca_certs() in Cesanta Mongoose before 7.2 allows remote attackers to cause a denial of service via TLS initialization where SSL_CTX_get_cert_store() returns NULL.

Impact

The primary impact of CVE-2025-65502 is denial of service, which can disrupt availability of services relying on Cesanta Mongoose for TLS communications. European organizations deploying Mongoose in IoT devices, embedded systems, or networked applications may experience service interruptions, potentially affecting critical infrastructure or business operations. Although the vulnerability does not expose sensitive data or allow unauthorized access, repeated exploitation could degrade trust in affected services and cause operational downtime. In sectors such as manufacturing, healthcare, or smart city infrastructure, where Mongoose might be embedded, this could lead to significant operational challenges. The ease of remote exploitation without authentication increases the risk profile, especially for exposed network services. However, the requirement for user interaction (e.g., initiating a TLS handshake) somewhat limits automated exploitation. Overall, the impact is moderate but relevant for organizations with critical TLS-dependent services using the affected library.

CWE-476NULL Pointer Dereference (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #13OWASP Top 10 A10:2025: Mishandling of Exceptional Conditions (opens in a new tab)
The product dereferences a pointer that it expects to be valid but is NULL.
Implementation
For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
Requirements
Select a programming language that is not susceptible to these issues.
Implementation
Check the results of all functions that return a value and verify that the value is non-null before acting upon it.
OWASP Cheat Sheets
Logging (opens in a new tab)
Error Handling (opens in a new tab)
OWASP ASVS 4.0.3
V11.1.7 (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 1 Dec 2025, 14:38 UTC

WeaknessesCWE-476

Technical details

References

Community reviews

Related threats