CVE-2026-5245
CVE-2026-5245 — Cesanta Mongoose mDNS Record mongoose.c handle_mdns_record stack-based overflow
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.
Published Updated Sources: cvelistV5, VulDB
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
1%
chance of exploitation in 30 days
CVSS base
5.6
MEDIUM
CISA SSVC assessment
Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.
Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script all four kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component
Affected scope
The catalog records vendors and products as separate lists, not pairs, so which product belongs to which vendor is not something this page can say.
Vendors (1)
Products (1)
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 5.6 | CVSS 3.1 | MEDIUM | — | — | cvelistV5 |
Weakness & attack patterns
- CWE-121
- CWE-119
References
6 on the record
- vuldb.com/vuln/354826
vdb-entry, technical-description
- vuldb.com/vuln/354826/cti
signature, permissions-required
- vuldb.com/submit/770103
third-party-advisory
- github.com/cesanta/mongoose/commit/0d882f1b43ff2308b7486a56a9d60cd6dba8a3f1
patch
- github.com/cesanta/mongoose/releases/tag/7.21
patch
- github.com/cesanta/mongoose/
product
Elsewhere on this site
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.