Vulnerability · Published Aug 27, 2026 · Assigned by VulnCheck

CVE-2026-81699openssl_encrypt before 1.4.9 Denial of Service via unbounded KDF cost

High 7.5

In plain English

A high-severity resource allocation without limits in openssl_encrypt from jahlives. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 43% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.5%top 56.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

openssl_encrypt versions before 1.4.9 fail to properly validate key derivation function costs in crafted files, allowing attackers to trigger unbounded memory and CPU exhaustion during pre-authentication processing. Attackers can supply malicious files with excessive KDF parameters to exhaust system resources and crash or wedge the process before password verification occurs.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	openssl-encrypt	1.4.9	PYSEC-2026-3961

Affected products (as reported)

Vendor	Product	Versions
jahlives	openssl_encrypt	0 – before 1.4.9

Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

References

GitHub Security Advisory (GHSA-phmr-p567-q5g6) vendor-advisory
VulnCheck Advisory: openssl_encrypt before 1.4.9 Denial of Service via unbounded KDF cost third-party-advisory