CVE-2026-81706: openssl_encrypt before 1.4.9 Key Substitution via Identity Shadowing
opensslencrypt before 1.4.9 fails to prevent namespace collisions between own identities and contacts in IdentityStore, allowing attackers to create shadowed contact entries invisible until the corresponding own identity is deleted. When the own identity is deleted, the shadowed contact becomes visible and resolves to the attacker's keys, enabling silent key substitution for encrypted files.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
openssl_encryptto a version that resolves this vulnerability.Fixed in 1.4.9
Event History
Frequently Asked Questions
Who is exposed to this issue?
Users of openssl_encrypt versions before 1.4.9 that use IdentityStore identities and contacts are exposed. The issue specifically affects environments where an attacker can create a contact entry whose identity collides with an existing own identity.
What does an attacker need to do to exploit it?
The attacker needs to create a shadowed contact entry using the same namespace as an own identity. Exploitation also depends on the corresponding own identity later being deleted, at which point the attacker-controlled contact becomes visible and its keys are used.
What is the security impact after the shadowed identity is revealed?
Encrypted files can silently resolve to attacker-controlled keys instead of the intended identity's keys. This can expose confidential data and allow integrity-impacting key substitution.
How can I determine whether I may already be affected?
Review IdentityStore for contact entries that collide with own identity namespaces, including entries that may have been hidden while the own identity existed. Pay particular attention to contacts that become visible after an own identity is deleted and verify the keys associated with those contacts.