What is CVE-2026-77838?

CVE-2026-77838 is a medium-severity vulnerability, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-08-28.

How severe is CVE-2026-77838?

Medium severity. CVSS v3 base score is 5.4 out of 10.

CVE-2026-77838

CVE-2026-77838

SOY Calendar contains a cross-site scripting vulnerability. An arbitrary script may be executed on the web browser of the user who is logging in to the product.

Vulnerability class: XSS (Cross-Site Scripting)

EPSS: 0.002 (6.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

vultures@jpcert.or.jp
vultures@jpcert.or.jp

Frequently asked questions

What is CVE-2026-77838?: CVE-2026-77838 is a medium-severity vulnerability, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2026-08-28.
How severe is CVE-2026-77838?: Medium severity. CVSS v3 base score is 5.4 out of 10.