What is CVE-2015-4000?A low-severity flaw in OpenSSL, explained.
CVE-2015-4000 is a low-severity flaw (CVSS 3.7) in OpenSSL, published on 21 May 2015. It is not on the list of flaws known to be exploited today. The latest forecast puts its chance of use in the next 30 days at over 99%. If you run an affected version, plan in the vendor’s fix.
Published 21 May 2015. Record last updated 12 April 2025. We keep this page's data up to date.
What is CVE-2015-4000? In plain terms.
It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can change some data.
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 kind of flaw is it?
- UnknownUnknown
How an attack on it works
Read straight from its severity rating, translated out of the shorthand.
- Where an attacker can beAnywhere on the internet
- How hard it is to pull offHard: conditions must line up
- Login needed firstNo login needed
- Does someone have to clickNo, nobody has to do anything
- What an attacker getsCan change some data
Severity vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Is CVE-2015-4000 being exploited? Not that we know of.
It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at over 99%. That can change at any time, which is why we keep watching.
Timeline
- Published
- Record last updated
CVE-2015-4000 scores 57. Action: Plan remediation.
We keep the score of every published flaw up to date as the evidence changes. Four things go into the score, and evidence that criminals are actually using it counts most. In order:
- Evidence it is being exploitedBiggest factor
- How severe it isStrong factor
- How widely exposed it isSmaller factor
- Threat activity around itSmaller factor
85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score.
When CVE-2015-4000 matches software you track, it lands in your list with its score and the reasons behind it.
See your own ranked list →Who is affected by CVE-2015-4000? 25 products.
The published record lists 25 products from 12 vendors. If you run one of these, check your version, then go to the fix below.
- Application
OpenSSL
by OpenSSL
Affected versionsup to 1.0.1m1.0.1 to 1.0.1m1.0.2 to 1.0.2a - Application
JDK
by Oracle
Affected versions1.6.0-update951.7.0-update751.7.0-update801.8.0-update_331.8.0-update45 - Application
JRE
by Oracle
Affected versions1.6.0-update_951.7.0-update_751.7.0-update_801.8.0-update_331.8.0-update_45 - Operating system
Ubuntu Linux
by Canonical
Affected versions12.0414.0414.1015.04 - Operating system
Debian Linux
by Debian
Affected versions7.08.0 - Application
Firefox
by Mozilla
Affected versions38.1.039.0 - Application
Thunderbird
by Mozilla
Affected versions31.838.1 - Application
Chrome
by Google
Affected versionsversion not specified - Application
Content Manager
by IBM
Affected versions8.5
How do I fix CVE-2015-4000? Four steps.
- Check whether you run itCompare your versions with the affected products above. Not sure what you run? Precursor Intelligence can work it out from your public website, or you can pick it from a list.
- Apply the vendor’s fixInstall the latest update from the vendor. The references list where the vendor has published details.
- If you can’t patch todayFollow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in.
- Keep an eye on itTrack the product and we tell you as soon as we spot this flaw on the list of exploited flaws, or a jump in its exploit likelihood.
References
49 linksDoes CVE-2015-4000 affect you? We'll keep checking.
Looking flaws up one at a time doesn't scale. Tell us what you run once, and we tell you which flaws matter to you, in what order, and keep watching for new ones.
- Tell us what you runPick your software from a list, or let us work it out from your website.
- We match it to every flawOver 400,000 published flaws, checked against your list.
- Ranked by real-world riskA 0 to 100 score, led by evidence criminals are using it.
- Told as soon as we knowAn alert by email, in the app or by webhook to your own tools.
Free plan, no card needed. Nothing to install.
1 new flaw affects software Acme tracks
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, whi...
- Matched to
- OpenSSL on Acme's software list
- What to do
- Plan in the vendor’s update
Sent to the alert recipients Acme chose. Also in the app and to Acme's webhook.
CVE-2015-4000 is a low-severity flaw in OpenSSL, published on 21 May 2015. It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can change some data.
It scores 3.7 out of 10 on the CVSS severity scale, which is low. Our risk score for CVE-2015-4000 is 57 out of 100, which is Medium. Its action is "Plan remediation". Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month.
It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at over 99%. That can change at any time, which is why we keep watching.
For OpenSSL: up to 1.0.1m, 1.0.1 to 1.0.1m, 1.0.2 to 1.0.2a. The record lists 25 products in all, each with its versions, under "Who is affected" on this page.
Install the update the vendor names in its advisory. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet.