CVE-2026-81703 openssl_encrypt before 1.4.9 Authentication Bypass via Unencrypted PQC Key

High 8.7 Published 27 Aug 2026 Updated 1 Oct 2026

Attackers can bypass authentication and decrypt data by crafting files with unencrypted post-quantum keys, affecting users of the openssl_encrypt library.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-81703?

CVE-2026-81703 is a high-severity authentication bypass vulnerability in Jahlives Openssl Encrypt, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official 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.

Weakness: CWE-287

Which versions are affected by CVE-2026-81703?

1 open source package ship an affected version, including openssl-encrypt. It affects 1 product.

Package	Affected	Fixed in
`openssl-encrypt` PyPI	All versions	`1.4.9`

Products include Jahlives Openssl Encrypt.

How do I fix CVE-2026-81703?

Upgrade openssl-encrypt to 1.4.9 or later.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2026-81703 being exploited?

There is no known exploitation of CVE-2026-81703 in the wild and no public exploit code.

All Jahlives Openssl Encrypt vulnerabilities

Sources

Also known as GHSA-crr6-63rq-gf5q, GHSA-qqfq-g2cv-j7v3, PYSEC-2026-3779.