CVE-2026-8406

openSIS Classic 9.3 contains an insecure direct object reference vulnerability in the messaging module. Any authenticated user with access to the messaging module can request sent-message details from modules/messaging/SentMail.php by supplying an arbitrary mail_id value.

CVSS 4.0

7.1CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

EPSS

0.2% chance of exploitation in the next 30 days; higher than 14% of CVEs (scores of 2026-10-25)

CWE

CWE-639

Published

2026-06-11

Modified

2026-10-26

Record from

the NVD, synced 2026-10-26

References

• https://fluidattacks.com/es/advisories/melanie
• https://github.com/OS4ED/openSIS-Classic
• https://github.com/OS4ED/openSIS-Classic/commit/c45d43146167324bae06bdf09de3e4bd2e5e478f
• https://fluidattacks.com/es/advisories/melanie

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