CVE-2021-25831

CRITICAL
9.8
CVSS Score
Published: March 1, 2021 at 03:08 PM UTC
Updated: June 17, 2026 at 03:42 AM UTC
1 product affected across 1 vendorDocument Server

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Severity
CRITICAL9.8
Exploit prediction
EPSS 12%

Description

A file extension handling issue was found in [core] module of ONLYOFFICE DocumentServer v4.0.0-9-v5.6.3. An attacker must request the conversion of the crafted file from PPTT into PPTX format. Using the chain of two other bugs related to improper string handling, a remote attacker can obtain remote code execution on DocumentServer.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

4.0.0-9 ≤ v ≤ 5.6.3

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
NVD-CWE-noinfo

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