Summary
generated automatically from NVD dataWAVLINK WN535M1 and WN535M3 routers with firmware prior to M35M1_V250922 have an unauthenticated arbitrary file write flaw in the sync_server daemon, which listens on TCP port 13136 and runs as root. The daemon takes a 100-byte filename field from its protocol header without path canonicalization, so a remote attacker can supply an absolute path and overwrite any file, such as startup scripts or credential stores, leading to persistent system compromise. The flaw is rated CRITICAL with a CVSS v3.1 score of 9.1 (CWE-36).
NVD description
WAVLINK WN535M1 and WN535M3 routers running firmware prior to M35M1_V250922 contain an unauthenticated arbitrary file write vulnerability that allows remote attackers to overwrite any file on the device by sending a crafted payload to the sync_server daemon on TCP port 13136. The daemon, which runs as root and requires no authentication, accepts a 100-byte filename field in its protocol header without path canonicalization, allowing attackers to supply an absolute path and write arbitrary content to overwrite startup scripts or credential stores to achieve persistent system compromise.
EPSS · FIRST.org
1.0%probability of exploitation in the next 30 days
Higher than 62% of scored CVEs
EPSS (Exploit Prediction Scoring System) estimates, from observed exploitation activity, how likely a CVE is to be exploited in the next 30 days. It complements CVSS, which measures severity, not likelihood. Score of 2026-10-16, recomputed daily by FIRST.org.
In-depth analysis on cveo.tech
We've published a detailed analysis of this CVE — exploitation, IOCs and mitigation.
CVSS v3.1 Score
Information
- Published
- 11 sept. 2026
- Updated
- 15 sept. 2026
- Status
- Deferred
- Source
- disclosure@vulncheck.com
Weaknesses (CWE)
Similar CVEs
Other vulnerabilities of type CWE-36
Monitor your products
Get automatic alerts for every new CVE affecting your equipment.