CVE-2018-0733: Incorrect CRYPTO_memcmp on HP-UX PA-RISC

Severity: medium (CVSS 5.9 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 8.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-03-27 · updated 2026-06-17

Description

Because of an implementation bug the PA-RISC CRYPTO_memcmp function is effectively reduced to only comparing the least significant bit of each byte. This allows an attacker to forge messages that would be considered as authenticated in an amount of tries lower than that guaranteed by the security claims of the scheme. The module can only be compiled by the HP-UX assembler, so that only HP-UX PA-RISC targets are affected. Fixed in OpenSSL 1.1.0h (Affected 1.1.0-1.1.0g).

Affected products

OpenSSL: from 1.1.0 through 1.1.0g

References

http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html
http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
http://www.securityfocus.com/bid/103517
http://www.securitytracker.com/id/1040576
https://git.openssl.org/gitweb/?p=openssl.git%3Ba=commitdiff%3Bh=56d5a4bfcaf37fa420aef2bb881aa55e61cf5f2f
https://security.gentoo.org/glsa/201811-21
https://security.netapp.com/advisory/ntap-20180330-0002/
https://www.openssl.org/news/secadv/20180327.txt
https://www.oracle.com/technetwork/security-advisory/cpuapr2019-5072813.html
https://www.oracle.com/technetwork/security-advisory/cpujan2019-5072801.html
https://www.oracle.com/technetwork/security-advisory/cpujul2019-5072835.html
https://www.tenable.com/security/tns-2018-04

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