Skip to main content

Mongoose CVE-2025-51495

HIGH
Integer Overflow or Wraparound (CWE-190)
2025-09-29 cve@mitre.org
7.5
CVSS 3.1 · NVD
View

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A06:2021 - Vulnerable and Outdated Components
ASVS 5.0
V15 - Secure Coding and Architecture Integer overflow checks
MITRE ATT&CK

1 technique across 1 tactic: Execution

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Impact

CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available. EPSS exploitation probability: 0.26%.

Exploit ScenarioDerived

A remote attacker could cause unexpected behavior through arithmetic overflow by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability.

This Month Plan within 30 days. Why: HIGH severity (CVSS 7.0-8.9).
Patch available 0.3% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Mar 28, 2026

An integer overflow vulnerability exists in the WebSocket component of Mongoose 7.5 thru 7.17. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Validate arithmetic operations, use safe integer libraries, check bounds before allocation.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified as Integer Overflow (CWE-190), which allows attackers to cause unexpected behavior through arithmetic overflow. An integer overflow vulnerability exists in the WebSocket component of Mongoose 7.5 thru 7.17. By sending a specially crafted WebSocket request, an attacker can cause the application to crash. If downstream vendors integrate this component improperly, the issue may lead to a buffer overflow. Affected products include: Cesanta Mongoose.

Know when Mongoose gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 7.5 HIGH
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Red Hat 7.5 MEDIUM

Primary rating from NVD.

CVSS VectorNVD

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

Lifecycle Timeline

3
Patch released
Mar 28, 2026 - 19:14 nvd
Patch available
PoC Detected
Oct 16, 2025 - 17:00 vuln.today
Public exploit code
CVE Published
Sep 29, 2025 - 17:15 nvd
HIGH 7.5

DescriptionCVE.org

An integer overflow vulnerability exists in the WebSocket component of Mongoose 7.5 thru 7.17. By sending a specially crafted WebSocket request, an attacker can cause the application to crash. If downstream vendors integrate this component improperly, the issue may lead to a buffer overflow.

Executive ViewAI

Why It Matters

CVE-2025-51495 presents notable security risk, a integer overflow vulnerability rated CVSS 7.5. Exploitation could allow attackers to corrupt memory, crash the application, or potentially execute arbitrary code. Proof-of-concept code is publicly available, increasing the risk of exploitation. A patch is available and should be applied as part of regular vulnerability management.

Business Impact: High
Compensating Controls

Apply vendor patch. If immediate patching is not feasible: (1) Implement network-level access controls to limit exposure; (2) Enable enhanced monitoring and alerting; (3) Apply principle of least privilege.

Threat Intelligence Overview

EPSS Score
0.3%
Top 50% exploitable
Exploit
POC
Public exploit code exists

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity HIGH
CISA KEV No
Public POC Yes
EPSS 0.3%
Patch available Yes
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Out-of-Cycle
Exploitation· derived
Poc
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact
High

Priority Score

58
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +38
PoC: +20
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

A buffer overflow occurs when a program writes more data to a memory buffer than it was allocated to hold, causing the excess data to spill into adjacent memory regions.

Integer overflow occurs when an arithmetic operation produces a result that exceeds the maximum value a given integer type can store.

Affected Products (CPE)CVE.org

cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*
CVE-2025-23061 CRITICAL POC
9.0 Jan 15

Mongoose ODM for Node.js before version 8.9.5 contains a search injection vulnerability when using $where filters with p

CVE-2017-2894 CRITICAL POC
9.8 Nov 07

An exploitable stack buffer overflow vulnerability exists in the MQTT packet parsing functionality of Cesanta Mongoose 6

CVE-2017-2891 CRITICAL POC
9.8 Nov 07

An exploitable use-after-free vulnerability exists in the HTTP server implementation of Cesanta Mongoose 6.8. Rated crit

CVE-2017-2922 CRITICAL POC
9.8 Nov 07

An exploitable memory corruption vulnerability exists in the Websocket protocol implementation of Cesanta Mongoose 6.8.

CVE-2017-2921 CRITICAL POC
9.8 Nov 07

An exploitable memory corruption vulnerability exists in the Websocket protocol implementation of Cesanta Mongoose 6.8.

CVE-2023-3696 CRITICAL POC
9.8 Jul 17

Prototype Pollution in GitHub repository automattic/mongoose prior to 7.3.4. Rated critical severity (CVSS 9.8), this vu

CVE-2022-2564 CRITICAL POC
9.8 Jul 28

Prototype Pollution in GitHub repository automattic/mongoose prior to 6.4.6. Rated critical severity (CVSS 9.8), this vu

CVE-2019-19307 CRITICAL POC
9.8 Nov 26

An integer overflow in parse_mqtt in mongoose.c in Cesanta Mongoose 6.16 allows an attacker to achieve remote DoS (infin

CVE-2024-53900 CRITICAL POC
9.1 Dec 02

Mongoose before 8.8.3 can improperly use $where in match, leading to search injection. Rated critical severity (CVSS 9.1

CVE-2021-26530 CRITICAL POC
9.1 Feb 08

The mg_tls_init function in Cesanta Mongoose HTTPS server 7.0 (compiled with OpenSSL support) is vulnerable to remote OO

CVE-2021-26529 CRITICAL POC
9.1 Feb 08

The mg_tls_init function in Cesanta Mongoose HTTPS server 7.0 and 6.7-6.18 (compiled with mbedTLS support) is vulnerable

CVE-2021-26528 CRITICAL POC
9.1 Feb 08

The mg_http_serve_file function in Cesanta Mongoose HTTP server 7.0 is vulnerable to remote OOB write attack via connect

Vendor StatusVendor

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy