LibreOffice up to 25.8.6/26.2.2 OOXML salt out-of-bounds write

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.0$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in LibreOffice up to 25.8.6/26.2.2. This impacts an unknown function of the component OOXML Handler. Executing a manipulation of the argument salt can lead to out-of-bounds write. This vulnerability is registered as CVE-2026-4430. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in LibreOffice up to 25.8.6/26.2.2. This vulnerability affects an unknown functionality of the component OOXML Handler. The manipulation of the argument salt with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Out-of-bounds write vulnerability in The Document Foundation LibreOffice via crafted OOXML documents with mismatched encryption salt parameters. This issue affects LibreOffice: from 26.2 before 26.2.3, from 25.8 before 25.8.7.

The weakness was published by Duc Anh Nguyen. The advisory is available at libreoffice.org. This vulnerability was named CVE-2026-4430 since 03/19/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit.

It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 313070 (Linux Distros Unpatched Vulnerability : CVE-2026-4430), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 25.8.7 or 26.2.3 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (313070) and CERT Bund (WID-SEC-2026-1393). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Debian Linux
  • Amazon Linux 2
  • Red Hat Enterprise Linux
  • Ubuntu Linux
  • Oracle Linux
  • RESF Rocky Linux
  • Open Source LibreOffice

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Proof-of-Concept

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 313070
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-4430

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: LibreOffice 25.8.7/26.2.3

Timelineinfo

03/19/2026 CVE reserved
05/07/2026 +48 days Advisory disclosed
05/07/2026 +0 days VulDB entry created
07/01/2026 +55 days VulDB entry last update

Sourcesinfo

Advisory: libreoffice.org
Researcher: Duc Anh Nguyen
Status: Confirmed

CVE: CVE-2026-4430 (🔒)
GCVE (CVE): GCVE-0-2026-4430
GCVE (VulDB): GCVE-100-361810
CERT Bund: WID-SEC-2026-1393 - LibreOffice: Schwachstelle ermöglicht nicht spezifizierten Angriff

Entryinfo

Created: 05/07/2026 10:12
Updated: 07/01/2026 13:44
Changes: 05/07/2026 10:12 (70), 05/07/2026 13:43 (7), 05/08/2026 04:07 (2), 07/01/2026 13:44 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Do you need the next level of professionalism?

Upgrade your account now!