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.
Fix
Patch, vendor advisory and mitigation references on NVD 1
- https://docs.wavlink.xyz/Security_Advisory/WAVLINK-SA-2026-091301/ patch, vendor-advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 1
- First seenCVSS 8.8 · wavlink technologyNVD modified 2026-10-29 17:47
Affected (CPE criteria) 0
NVD has not attached CPE configurations yet.
References 3
- https://github.com/camdsmith/wavlink-sync_server-rce/blob/main/README.md technical-description, exploit
- https://docs.wavlink.xyz/Security_Advisory/WAVLINK-SA-2026-091301/ patch, vendor-advisory
- https://www.vulncheck.com/advisories/wavlink-wn535m1-wn535m3-unauthenticated-arbitrary-file-write-via-sync-server third-party-advisory