CVE-2025-9303: TOTOLINK A720R · Buffer Overflow
Affects TOTOLINK A720RSource CVE Database V5
Not known to be exploited · CVSS 8.7 High.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.8% chance of exploitation in 30 days – higher than 59% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 21 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
AI-suggested
Organizations should immediately inventory their network to identify any TOTOLINK A720R devices running the vulnerable firmware version 4.1.5cu.630_B20250509. Until an official patch is released, it is critical to restrict remote access to the router's management interface, ideally limiting it to trusted IP addresses or disabling remote management entirely. Network segmentation should be enforced to isolate vulnerable devices from critical assets. Monitoring network traffic for unusual patterns or signs of exploitation attempts targeting /cgi-bin/cstecgi.cgi can provide early detection. Employing intrusion detection/prevention systems (IDS/IPS) with updated signatures for this vulnerability can help block exploit attempts. Users should consider replacing vulnerable devices with models from vendors with timely security updates if patching is not forthcoming. Additionally, applying strict firewall rules to block unsolicited inbound traffic to the router and enforcing strong authentication for local access can reduce exploitation risk. Organizations should stay alert for vendor advisories and apply patches immediately upon release.
Description
A security flaw has been discovered in TOTOLINK A720R 4.1.5cu.630_B20250509. This issue affects the function setParentalRules of the file /cgi-bin/cstecgi.cgi. Performing manipulation of the argument desc results in buffer overflow. The attack is possible to be carried out remotely. The exploit has been released to the public and may be exploited.
References
- vuldb.com (opens in a new tab)
- vuldb.com (opens in a new tab)
- vuldb.com (opens in a new tab)
- github.com/lin-3-start/lin-cve/blob/main/TOTOLINK%20A720R/TOTOLINK-A720R.md (opens in a new tab)
- github.com/lin-3-start/lin-cve/blob/main/TOTOLINK%20A720R/TOTOLINK-A720R.md (opens in a new tab)
- totolink.net (opens in a new tab)