CVE-2018-0733
Incorrect CRYPTO_memcmp on HP-UX PA-RISC
CVE-2018-0733 is a medium vulnerability (CVSS 5.9) in Openssl, published March 27, 2018. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 8.28%, the 95th percentile. Fixed in openssl 1.0.2o-r0.
- Severity
- 5.9 MediumCVSS 3.0, NVD
- Exploit chance
- 8.28%EPSS, 95th percentile
- Exploitation
- None knownNot on CISA’s or ENISA’s lists
- Fixed in
1.0.2o-r0openssl +8 more
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).
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
opensslAlpine:v3.3 | 1.1.0 up to 1.0.2o-r0 | 1.0.2o-r0 |
opensslAlpine:v3.4 | 1.1.0 up to 1.0.2o-r0 | 1.0.2o-r0 |
opensslAlpine:v3.5 | 1.1.0 up to 1.0.2o-r0 | 1.0.2o-r0 |
opensslAlpine:v3.6 | 1.1.0 up to 1.0.2o-r0 | 1.0.2o-r0 |
opensslAlpine:v3.7 | 1.1.0 up to 1.0.2o-r0 | 1.0.2o-r0 |
opensslAlpine:v3.8 | 1.1.0 up to 1.0.2o-r0 | 1.0.2o-r0 |
opensslDebian:12 | before 1.1.0h-1 | 1.1.0h-1 |
opensslDebian:13 | before 1.1.0h-1 | 1.1.0h-1 |
opensslDebian:14 | before 1.1.0h-1 | 1.1.0h-1 |
What each source reports
NVD Score used
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).
- Record
CVE-2018-0733- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:P/A:N - Updated
- 2026-11-02
CVE ListNo score
Incorrect CRYPTO_memcmp on HP-UX PA-RISC
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).
- Record
CVE-2018-0733- Updated
- 2026-11-02
EUVDEUVD-2018-1543No score
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).
- Record
EUVD-2018-1543- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-j66x-3v7r-hj5f
Because of an implementation bug the PA-RISC CRYPTO_memcmp function is effectively reduced to...
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).
- Record
GHSA-j66x-3v7r-hj5f- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVALPINE-CVE-2018-0733
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).
- Record
ALPINE-CVE-2018-0733- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVBELL-CVE-2018-0733
CVE-2018-0733 does not affect BellSoft software
- Record
BELL-CVE-2018-0733- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSV
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).
- Record
CVE-2018-0733- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-11
OSVDEBIAN-CVE-2018-0733
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).
- Record
DEBIAN-CVE-2018-0733- CVSS 3.0
- 5.9 Medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
References
tenable.com/security/tns-2018-07
oracle.com/technetwork/security-advisory/cpujul2018-4258247.html
security.gentoo.org/glsa/201811-21
securityfocus.com/bid/103517
Show 14 moreShow less
security.netapp.com/advisory/ntap-20180330-0002
securitytracker.com/id/1040576
git.openssl.org/gitweb?p=openssl.git%3Ba=commitdiff%3Bh=56d5a4bfcaf37fa420aef2bb881aa55e61cf5f2f
openssl.org/news/secadv/20180327.txt
nvd.nist.gov/vuln/detail/CVE-2018-0733
github.com/advisories/GHSA-j66x-3v7r-hj5f
security.alpinelinux.org/vuln/CVE-2018-0733
docs.bell-sw.com/security/cves/CVE-2018-0733
security-tracker.debian.org/tracker/CVE-2018-0733