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TI-2026-60325 Aliases CVE-2026-89009GHSA-pg3c-cqw3-4pgg

WAVLINK WN535M1/WN535M3 Unauthenticated Arbitrary File Write via sync_server

Priority HIGH 77CWE-36Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
None · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.01011 63rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by the CNA
Fix Fixed WN535M1 (WAVLINK Technology): M35M1_V250922WN535M3 (WAVLINK Technology): M35M1_V250922

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
WavlinkWN535M1M35M1_V210223M35M1_V250922Patch availableCNA
WavlinkWN535M3M35M1_V210223M35M1_V250922Patch availableCNA
  • WN535M1 VendorWavlink Affected M35M1_V210223 Fixed in M35M1_V250922 Patch available CNA
  • WN535M3 VendorWavlink Affected M35M1_V210223 Fixed in M35M1_V250922 Patch available CNA

Remediation

  • Fix · CNA WN535M1 (WAVLINK Technology) Fixed in M35M1_V250922
  • Fix · CNA WN535M3 (WAVLINK Technology) Fixed in M35M1_V250922

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-89009
  2. 2026-10-03 Alias added: GHSA-pg3c-cqw3-4pgg
  3. 2026-10-29 1 new reference · CNA

References

Exploit 1

Patch 1

  • TI-2022-02298 WAVLINK WN535K2/WN535K3 nightled.cgi os command injection CVSS 3.1CRITICAL 9.8
  • TI-2026-83752 OS command injection in WAVLINK WN551X3-A DNS resolution handler CVSS 4.0CRITICAL 10.0
  • TI-2026-83751 WAVLINK WN551X3-A WireGuard CLI Group ioos os command injection CVSS 4.0CRITICAL 10.0
  • TI-2026-83668 Stack-based overflow in WAVLINK WN536AX6-A OpenVPN handler CVSS 4.0CRITICAL 10.0
  • TI-2026-83667 OS command injection in WAVLINK WN536AX6-A WireGuard handler CVSS 4.0CRITICAL 10.0
  • TI-2026-83666 OS command injection in WAVLINK WN536AX6-A openvpn_cli handler CVSS 4.0CRITICAL 10.0
See all 248 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences