Denial of Service in OpenSSL Encrypt Versions by OpenSSL
CVE-2026-81699

8.7HIGH

Key Information:

Vendor

Jahlives

Status
OpenSSL Encrypt
Vendor
CVE Published:
27 August 2026

What is CVE-2026-81699?

The unpatched versions of openssl_encrypt before 1.4.9 are vulnerable to a denial of service attack stemming from improper validation of key derivation function (KDF) costs. Attackers can exploit this vulnerability by supplying maliciously crafted files with excessive KDF parameters, leading to unbounded memory and CPU exhaustion during pre-authentication processing. This can result in resource exhaustion, causing the system to crash or become unresponsive before password verification takes place.

Affected Version(s)

openssl_encrypt 0 < 1.4.9

openssl_encrypt 1.4.9

References

https://github.com/jahlives/openssl_encrypt/security/advi...
vendor-advisory
https://www.vulncheck.com/advisories/openssl-encrypt-befo...
third-party-advisory

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
High
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.