Skip to main content

Mongoose CVE-2026-5245

| EUVDEUVD-2026-18183 LOW
Stack-based Buffer Overflow (CWE-121)
2026-04-02 VulDB
2.9
CVSS 4.0 · NVD

Severity by source

NVD PRIMARY
2.9 LOW
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
X

Lifecycle Timeline

7
Severity Changed
Apr 29, 2026 - 01:11 NVD
MEDIUM LOW
CVSS changed
Apr 29, 2026 - 01:11 NVD
6.3 (MEDIUM) 2.9 (LOW)
PoC Detected
Apr 03, 2026 - 16:10 vuln.today
Public exploit code
EUVD ID Assigned
Apr 02, 2026 - 09:30 euvd
EUVD-2026-18183
Analysis Generated
Apr 02, 2026 - 09:30 vuln.today
Patch released
Apr 02, 2026 - 09:30 nvd
Patch available
CVE Published
Apr 02, 2026 - 09:00 nvd
MEDIUM 6.3

DescriptionCVE.org

A vulnerability was found in Cesanta Mongoose up to 7.20. This impacts the function handle_mdns_record of the file mongoose.c of the component mDNS Record Handler. Performing a manipulation of the argument buf results in stack-based buffer overflow. Remote exploitation of the attack is possible. A high degree of complexity is needed for the attack. The exploitability is said to be difficult. The exploit has been made public and could be used. Upgrading to version 7.21 will fix this issue. The patch is named 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1. You should upgrade the affected component. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.

AnalysisAI

Stack-based buffer overflow in Cesanta Mongoose mDNS Record Handler (versions up to 7.20) allows remote attackers to trigger memory corruption via malformed mDNS record data in the handle_mdns_record function. The vulnerability requires high attack complexity and network-level access but results in limited confidentiality, integrity, and availability impact. Publicly available exploit code exists; vendor released patched version 7.21 with immediate availability.

Technical ContextAI

The vulnerability exists in the mDNS (Multicast DNS) record handling component of Mongoose, a lightweight embedded networking library. The root cause is a stack-based buffer overflow (CWE-121) in the handle_mdns_record function of mongoose.c, triggered by improper bounds checking when processing the buf argument during mDNS packet parsing. The affected CPE cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:* indicates all Mongoose versions through 7.20 are vulnerable. mDNS operates at the application layer for service discovery and hostname resolution; the overflow occurs during record deserialization, allowing attackers on the network to craft malicious mDNS packets that overwrite stack memory adjacent to the vulnerable buffer.

RemediationAI

Vendor-released patch: upgrade Cesanta Mongoose to version 7.21 or later. The fix is available at https://github.com/cesanta/mongoose/releases/tag/7.21, with the commit hash 0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1 for upstream verification. Immediately update all Mongoose-based applications and embedded systems to version 7.21. No workarounds are documented; patching is the only remediation. Verify the update by checking Mongoose version in application startup logs or embedded firmware manifests. For air-gapped or legacy deployments unable to upgrade immediately, restrict untrusted mDNS traffic at the network boundary (e.g., firewall rules blocking UDP 5353 from external sources).

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

Share

CVE-2026-5245 vulnerability details – vuln.today

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