Critical severity · published Oct 5, 2026
CVE-2026-91107
openSIS Classic 9.3 - Insecure Direct Object Reference (IDOR)
9.3
CVSS
0.2%
EPSS
No
On KEV
Description
openSIS Classic 9.3 allows an authenticated user with the built-in teacher role can select an arbitrary staff record through staff_id and cause the School Information update path to reset that selected account's password.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 15% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
openSIS-Classic · OS4ED
9.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91107
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91107
third-party-advisory
https://fluidattacks.com/advisories/hearts
product
https://github.com/OS4ED/openSIS-Classic
patch
https://github.com/OS4ED/openSIS-Classic/commit/24bb530391a67c114cd4fe3dff65da7e070f5ed1
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