CVE-2021-29088

Local code execution via CGI path traversal

Published Jun 1, 2021 · Updated Sep 16, 2024

Path traversal in the cgi component of Synology DiskStation Manager before 6.2.4-25553 allows local users to execute arbitrary code. Synology has not disclosed the affected CGI endpoint or the pathname operation that fails to confine attacker-controlled input. A low-privileged local account is required, and successful exploitation runs code in the DSM appliance context.

CVSS severity7.8
High
EPSS probability0.32%
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 the cgi component of Synology DiskStation Manager before 6.2.4-25553 allows local users to execute arbitrary code. Synology has not disclosed the affected CGI endpoint or the pathname operation that fails to confine attacker-controlled input. A low-privileged local account is required, and successful exploitation runs code in the DSM appliance context.

The record

CVE
CVE-2021-29088
Published
Jun 1, 2021
Updated
Sep 16, 2024
Vendor
Synology
Product
Synology DiskStation Manager
Classifications
CWE-22, CAPEC-76, CAPEC-126, CAPEC-79, CAPEC-64, CAPEC-78
Attack vector
local
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 vectorlocal
Required privilegesauthenticated

What is affected?

Synology · Synology DiskStation Managerversion=unspecified <6.2.4-25553

Published CVSS scores

7.8Synology Inc.CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
4.6NIST NVDAV:L/AC:L/Au:N/C:P/I:P/A:P

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CAPEC-76Manipulating Web Input to File System Calls
CAPEC-126Path Traversal
CAPEC-79Using Slashes in Alternate Encoding
CAPEC-64Using Slashes and URL Encoding Combined to Bypass Validation Logic
CAPEC-78Using Escaped Slashes in Alternate Encoding

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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