Critical 9.1Published Sep 11, 2026

CVE-2026-89009WAVLINK WN535M1/WN535M3 Unauthenticated Arbitrary File Write via sync_server

Updated under an hour ago (2026-10-19 08:50 UTC)

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It affects WAVLINK Technology WN535M1 and 1 other product. Add what you run to find out whether that includes you.

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Every CVE for WAVLINK Technology WN535M1

Exploited in the last 30 days

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.

CVSS: 9.1 CRITICAL (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Weakness (CWE): CWE-36
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Deferred
Record last updated: Sep 15, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

WAVLINK Technology WN535M1 wavlink_technology:wn535m1 (from the name)	M35M1_V210223; M35M1_V250922 not affected	CNA record
WAVLINK Technology WN535M3 wavlink_technology:wn535m3 (from the name)	M35M1_V210223; M35M1_V250922 not affected	CNA record

References

https://github.com/camdsmith/wavlink-sync_server-rce/blob/main/README.mdtechnical-description, exploit
https://docs.wavlink.xyz/product, patch
https://www.vulncheck.com/advisories/wavlink-wn535m1-wn535m3-unauthenticated-arbitrary-file-write-via-sync-serverthird-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.