CVE-2026-81688

high

Description

openssl_encrypt versions before 1.4.9 store an unkeyed SHA-256 hash of the plaintext in the cleartext file header metadata. Attackers can read this hash without the password to confirm guessed plaintexts offline or fingerprint identical plaintexts across separately-encrypted files.

References

https://www.vulncheck.com/advisories/openssl-encrypt-before-1.4.9-plaintext-confirmation-oracle-via-sha-256

https://github.com/jahlives/openssl_encrypt/security/advisories/GHSA-7c3q-gp4v-q29q

Details

Source: Mitre, NVD

Published: 2026-08-27

Updated: 2026-08-28

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Severity: High

CVSS v4

Base Score: 8.7

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00198