Buffer overflow in Canon Marketing Japan Inc. Guardianwall Mail Security Cloud (Saas Version)

CVE-2026-32661

Stack-based buffer overflow vulnerability exists in GUARDIANWALL MailSuite and GUARDIANWALL Mail Security Cloud (SaaS version). If a remote attacker sends a specially crafted request to the product's web service, arbitrary code may be executed when the product is configured to run pop3wallpasswd with grdnwww user privilege.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.007 (52.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 52.4% 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-2026-32661: held from 0.005 to 0.007.

EPSS over last 30 days · oldest: 0.005 · newest: 0.007 · change: +0.003

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-32661?
CVE-2026-32661 is a critical-severity vulnerability in Canon Marketing Japan Inc. Guardianwall Mail Security Cloud (Saas Version), classified under Stack-based Buffer Overflow. CVSS score: 9.8/10. Published 2026-05-13.
How severe is CVE-2026-32661?
Critical severity. CVSS v3 base score is 9.8 out of 10.