CVE-2021-33182Network attack vector

Authenticated file disclosure via PDF path traversal

Published Jun 1, 2021 · Updated Sep 16, 2024

Path traversal in Synology DiskStation Manager PDF Viewer before 6.2.4-25553 allows remote authenticated users to read limited files. PDF Viewer fails to confine an attacker-controlled pathname to its intended directory, but Synology has not disclosed the affected request or code locus. Authenticated network access to PDF Viewer is required, and successful exploitation exposes only files reachable through the undisclosed traversal path.

CVSS severity5.0
Medium
EPSS probability1.11%
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 Synology DiskStation Manager PDF Viewer before 6.2.4-25553 allows remote authenticated users to read limited files. PDF Viewer fails to confine an attacker-controlled pathname to its intended directory, but Synology has not disclosed the affected request or code locus. Authenticated network access to PDF Viewer is required, and successful exploitation exposes only files reachable through the undisclosed traversal path.

The record

CVE
CVE-2021-33182
Published
Jun 1, 2021
Updated
Sep 16, 2024
Vendor
Synology
Product
Synology DiskStation Manager
Classifications
CWE-22, T1005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 1, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <6.2.4-25553

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Synology · Synology DiskStation Managerversion=unspecified <6.2.4-25553

Published CVSS scores

5.0Synology Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N
4.0NIST NVDAV:N/AC:L/Au:S/C:P/I:N/A:N
4.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitUnconfirmed

Weakness, pattern, technique

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

Public exploit references

No public exploit references are available in this record.

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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