OS4ED openSIS-Classic 9.3 Messaging SentMail.php authorization

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.1$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in OS4ED openSIS-Classic 9.3. Impacted is an unknown function of the file modules/messaging/SentMail.php of the component Messaging Module. The manipulation results in authorization. This vulnerability is identified as CVE-2026-8406. The attack can be executed remotely. There is not any exploit available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability classified as problematic has been found in OS4ED openSIS-Classic 9.3. Affected is some unknown functionality of the file modules/messaging/SentMail.php of the component Messaging Module. The manipulation with an unknown input leads to a authorization vulnerability. CWE is classifying the issue as CWE-639. The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data. This is going to have an impact on confidentiality. CVE summarizes:

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.

The weakness was released by Daniel Celis. The advisory is available at fluidattacks.com. This vulnerability is traded as CVE-2026-8406 since 05/12/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit.

By approaching the search of inurl:modules/messaging/SentMail.php it is possible to find vulnerable targets with Google Hacking.

Applying the patch c45d43146167324bae06bdf09de3e4bd2e5e478f is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-36245). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

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Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Authorization
CWE: CWE-639 / CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Google Hack: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: c45d43146167324bae06bdf09de3e4bd2e5e478f

Timelineinfo

05/12/2026 CVE reserved
06/11/2026 +30 days Advisory disclosed
06/11/2026 +0 days VulDB entry created
06/11/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: fluidattacks.com
Researcher: Daniel Celis
Status: Confirmed

CVE: CVE-2026-8406 (🔒)
GCVE (CVE): GCVE-0-2026-8406
GCVE (VulDB): GCVE-100-370386
EUVD: 🔒

Entryinfo

Created: 06/11/2026 16:37
Updated: 06/11/2026 19:08
Changes: 06/11/2026 16:37 (69), 06/11/2026 19:08 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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