Buffer overflow in Totolink A720r

CVE-2025-9303

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.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (56.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 57th percentile — 56.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-9303: held from 0.008 to 0.009.

EPSS over last 30 days · oldest: 0.008 · newest: 0.009 · change: +0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-9303?
CVE-2025-9303 is a high-severity vulnerability in Totolink A720r, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 8.8/10. Published 2025-08-21.
How severe is CVE-2025-9303?
High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2025-9303 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.