CVE-2023-34939Public exploitNetwork attack vector

Unauthenticated code execution via upload path traversal

Published Jun 22, 2023 · Updated Dec 6, 2024

Path traversal in ONLYOFFICE Community Server before 12.5.2 allows remote attackers to execute arbitrary code through UploadProgress.ashx. The upload handler accepts ../ sequences in a multipart filename and writes the supplied ASPX file outside the intended upload directory. Exploitation requires an existing forum thread; successful writes place attacker-controlled server-side code in the web root.

CVSS severity9.8
Critical
EPSS probability5.03%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Path traversal in ONLYOFFICE Community Server before 12.5.2 allows remote attackers to execute arbitrary code through UploadProgress.ashx. The upload handler accepts ../ sequences in a multipart filename and writes the supplied ASPX file outside the intended upload directory. Exploitation requires an existing forum thread; successful writes place attacker-controlled server-side code in the web root.

The record

CVE
CVE-2023-34939
Published
Jun 22, 2023
Updated
Dec 6, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-22, T1505.003, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 22, 2023CVE publishedPublication date reported by the CVE source.
  2. Dec 6, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1505.003Server Software Component: Web Shell
T1190Exploit Public-Facing Application

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo