CVE-2026-81703

Severity CVSS v4.0:

HIGH

Type:

CWE-287 Authentication Issues

Publication date:

27/08/2026

Last modified:

28/08/2026

Description

openssl_encrypt versions before 1.4.9 fail to validate encryption status of embedded post-quantum private keys in file metadata. Attackers can craft files with unencrypted embedded PQC keys that decrypt under any password, bypassing authentication and producing attacker-chosen plaintext with false integrity verification.

Impact

Vector 4.0

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

Base Score: 8.70 HIGH
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

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

Base Score 4.0

8.70

Severity 4.0

HIGH

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N CVSS v3.1 Severity and Metrics:

Base Score: 5.50 MEDIUM
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): High
Availability (A): None

Base Score 3.x

5.50

Severity 3.x

MEDIUM

CVE-2026-81703

Description

Impact

References to Advisories, Solutions, and Tools