AUGUST 4, 2026
Live Feed
Back to database
Case File

CVE-2021-25831

CRITICAL · CVSS 9.8 EPSS 11.50% Public Exploit

Source: NVD + CISA KEV + EPSS (historical backfill) · Published 2021-03-01 · Last synced 2026-08-04

CyberRota Analysis

AI analysis pending.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
remote code execution code execution

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2021-25831
Severity
CRITICAL
CVSS
9.8
EPSS
11.50%
Office

Original NVD 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.