CVE-2026-118673

Severity CVSS v4.0:

MEDIUM

Type:

CWE-787 Out-of-bounds Write

Publication date:

29/10/2026

Last modified:

03/11/2026

Description

KeePassXC is a cross-platform community-driven port of the Windows application KeePass Password Safe. From 2.3.0 until 2.8.0, KeePassXC browser integration encrypts authorized responses in src/browser/BrowserMessageBuilder.cpp using a fixed 1 MiB output vector even though Botan::Sodium::crypto_box_easy() writes the plaintext length plus crypto_box_MACBYTES. A browser-protocol client that can access the per-user IPC endpoint, has a valid database association, and causes an unlocked database to generate and encrypt a sufficiently large authorized response can trigger a sequential out-of-bounds write before any response is delivered. This issue is fixed in version 2.8.0.

Impact

Vector 4.0

CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N CVSS v4.0 Severity and Metrics:

Base Score: 4.10 MEDIUM
Vector: CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Attack Vector (AV): Local
Attack Complexity (AC): High
Attack Requirements (AT): Present
Privileges Required (PR): Low
User Interaction (UI): Passsive
Confidentiality (VC): None
Integrity (VI): None
Availability (VA): High
Confidentiality (SC): None
Integrity (SI): None
Availability (SA): None

Base Score 4.0

4.10

Severity 4.0

MEDIUM

CVE-2026-118673

Description

Impact

References to Advisories, Solutions, and Tools