CVE-2021-43449Public exploitNetwork attack vector

Arbitrary URL reads via WebSocket document conversion

Published Jan 23, 2023 · Updated Apr 2, 2025

SSRF in ONLYOFFICE Document Server before 7.2 allows remote attackers to read arbitrary URL responses through the document editor. The auth WebSocket command accepts an attacker-supplied original-document URL, and the converter fetches and renders its response without destination restrictions. An unauthenticated WebSocket connection can reach internal HTTP services, cloud metadata endpoints, or attacker-controlled hosts.

CVSS severity8.1
High
EPSS probability1.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

SSRF in ONLYOFFICE Document Server before 7.2 allows remote attackers to read arbitrary URL responses through the document editor. The auth WebSocket command accepts an attacker-supplied original-document URL, and the converter fetches and renders its response without destination restrictions. An unauthenticated WebSocket connection can reach internal HTTP services, cloud metadata endpoints, or attacker-controlled hosts.

The record

CVE
CVE-2021-43449
Published
Jan 23, 2023
Updated
Apr 2, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-918, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 23, 2023CVE publishedPublication date reported by the CVE source.
  2. Apr 2, 2025Record 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 privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.1CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
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

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Your stack

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