CVE-2026-27850 json
Improper verification in Linksys MR9600, Linksys MX4200
published 8mo ago modified 4mo ago also EUVD-2026-8698
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
Due to an improperly configured firewall rule, the router will accept any connection on the WAN port with the source port 5222, exposing all services which are normally only accessible through the local network. This issue affects MR9600: 1.0.4.205530; MX4200: 1.0.13.210200.
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 8mo ago
Exploit prediction
0.28% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N |
Affected products
- Linksys MR9600
- Linksys MX4200
References
-
syss.de
/fileadmin/dokumente/Publikationen/Advisories/SYSS-2025-014.txt
third-party-advisory, technical-description
Sources
- CVE List CVE-2026-27850
- NVD CVE-2026-27850
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