An improper binary stream data handling issue was found in the [core] module of…
Priority MEDIUM 43Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
An improper binary stream data handling issue was found in the [core] module of ONLYOFFICE DocumentServer v4.0.0-9-v5.6.3. Using this bug, an attacker is able to produce a denial of service attack that can eventually shut down the target server.
Why it matters now
EPSS 0.07445 94th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:onlyoffice:document_server:*:*:*:*:*:*:*:* | 4.0.0-9 – 5.6.3 | Vulnerable | ONLYOFFICE |
- cpe:2.3:a:onlyoffice:document_server:*:*:*:*:*:*:*:* Versions 4.0.0-9 – 5.6.3 Vulnerable ·ONLYOFFICE
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2021-25829
- 2026-10-03 Alias added: GHSA-jmxf-5qxj-85w9
References
Advisory 8
- https://github.com/ONLYOFFICE/core
- https://github.com/ONLYOFFICE/core/blob/v5.6.4.10/ASCOfficePPTXFile/Editor/BinaryFileReaderWriter.cpp#L1722
- https://github.com/ONLYOFFICE/core/blob/c1e4a2ce33bdcfab29d670f5fdb10fc63cf5fd6a/ASCOfficePPTXFile/PPTXFormat/Comments.h#L299
- https://github.com/ONLYOFFICE/core/blob/c1e4a2ce33bdcfab29d670f5fdb10fc63cf5fd6a/ASCOfficePPTXFile/PPTXFormat/Core.h#L161
- https://github.com/ONLYOFFICE/core/blob/c1e4a2ce33bdcfab29d670f5fdb10fc63cf5fd6a/ASCOfficePPTXFile/PPTXFormat/NotesMaster.h#L148
- https://github.com/ONLYOFFICE/core/blob/c1e4a2ce33bdcfab29d670f5fdb10fc63cf5fd6a/ASCOfficePPTXFile/PPTXFormat/NotesSlide.h#L141
- https://github.com/ONLYOFFICE/core/blob/c1e4a2ce33bdcfab29d670f5fdb10fc63cf5fd6a/ASCOfficePPTXFile/PPTXFormat/Presentation.h#L277
- https://github.com/ONLYOFFICE/core/blob/c1e4a2ce33bdcfab29d670f5fdb10fc63cf5fd6a/ASCOfficePPTXFile/PPTXFormat/Theme.h#L277
More ONLYOFFICE Document Server vulnerabilities
- TI-2021-02273 Path traversal in ONLYOFFICE Document Server enables code execution KEVCVSS 3.1CRITICAL 9.8
- TI-2023-14162 An out of bounds memory access vulnerability in ONLYOFFICE DocumentServer 4.0.3 through… CVSS 3.1CRITICAL 9.8
- TI-2023-14161 A use after free issue discovered in ONLYOFFICE DocumentServer 4.0.3 through 7.3.2 allows… CVSS 3.1CRITICAL 9.8
- TI-2023-14163 Memory Exhaustion vulnerability in ONLYOFFICE Document Server 4.0.3 through 7.3.2 allows… CVSS 3.1HIGH 7.5
- TI-2021-07886 A file extension handling issue was found in [server] module of ONLYOFFICE DocumentServer… CVSS 3.1CRITICAL 9.8
- TI-2023-25368 Path Traversal vulnerability in ONLYOFFICE Document Server before v8.0.1 allows a remote… CVSS 3.1MEDIUM 6.7
Sources
- CVE-2021-25829 · CVE Program
- CVE-2021-25829 · NVD
- FIRST EPSS
- GHSA-jmxf-5qxj-85w9 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences