openssl_encrypt EUVD-2026-67055

The target service must accept attacker-supplied encrypted files or data blobs for processing and pass them through the jahlives/openssl_encrypt library before authentication completes - exploitation occurs entirely at the pre-authentication stage. The service must be running jahlives/openssl_encrypt specifically (not OpenSSL directly) at a version prior to 1.4.9. Limiting factors: the library must be the one performing KDF operations (not a higher-level framework that sanitizes inputs first); the file intake endpoint must be network-reachable without prior authentication; and the attack requires repeated or large submissions to sustain exhaustion against well-resourced servers. No special platform, operating system, or non-default configuration is required beyond the library being present and reachable.

The CVSS 4.0 score of 8.7 reflects network-reachable, unauthenticated, zero-interaction exploitation - signals that normally indicate high urgency. However, the provided CVSS 4.0 vector contains a material inconsistency that must be flagged: it records VC:H (high confidentiality impact) with VA:N (no availability impact), directly contradicting the vulnerability description, which describes a pure denial-of-service with no information disclosure. This appears to be a scoring error and should be verified against the vendor advisory before operationalizing the score. Correcting for this, the actual risk profile is a high-availability-impact DoS (assessed below as A:H). No EPSS data was supplied; no CISA KEV listing exists; no public exploit code has been identified. Real-world risk is meaningful for services that accept attacker-supplied encrypted files pre-authentication, but the library's limited enterprise footprint substantially constrains aggregate exposure.

An attacker submits a specially crafted encrypted file to any network-accessible endpoint backed by the jahlives/openssl_encrypt library. The file contains KDF parameters with extreme cost values (e.g., a scrypt N parameter of 2^30); the library begins key derivation pre-authentication, allocating gigabytes of memory and saturating CPU cores, ultimately crashing or permanently wedging the server process. No authentication or prior account access is required, and the attack is repeatable to sustain denial of service.