CVE-2021-40651Public exploitNetwork attack vector

Authenticated file disclosure via modname path traversal

Published Sep 29, 2021 · Updated Aug 4, 2024

Path traversal in OS4Ed openSIS Community 8.0 allows remote authenticated users to read arbitrary server files via the modname parameter. Modules.php accepts encoded parent-directory sequences in modname and resolves the supplied value outside the intended modules directory. Parent-level access is sufficient, and disclosure is limited to files readable by the application's server process.

CVSS severity6.5
Medium
EPSS probability17.95%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in OS4Ed openSIS Community 8.0 allows remote authenticated users to read arbitrary server files via the modname parameter. Modules.php accepts encoded parent-directory sequences in modname and resolves the supplied value outside the intended modules directory. Parent-level access is sufficient, and disclosure is limited to files readable by the application's server process.

The record

CVE
CVE-2021-40651
Published
Sep 29, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-22, T1005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
4.0NIST NVDAV:N/AC:L/Au:S/C:P/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1005Data from Local System

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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