CVE-2026-89009: WAVLINK WN535M1/WN535M3 Unauthenticated Arbitrary File Write via sync_server
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.
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cwe · low confidence lookup
CWE-36: Exact CWE lookup
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The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
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CWE-36 · source CWE mapping
Absolute Path Traversal
Absolute Path Traversal represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.