CVE-2015-4000
nss - security update
3.7
LOW
CVSS 3.1
EPSS 92.3%
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.
How to fix CVE-2015-4000
To remediate CVE-2015-4000, upgrade the affected package to a fixed version below.
- —upgrade to 2:3.19.1-1 or later
- —upgrade to 2:3.14.5-1+deb7u7 or later
- —upgrade to 2:3.26-1+debu8u1 or later
- —upgrade to 1.0.2b-1 or later
Is CVE-2015-4000 being exploited?
Likely — EPSS is 92.3%, placing CVE-2015-4000 in the top tier of vulnerabilities by exploitation probability. Prioritise patching.
Affected packages (4)
- from 0, < 2:3.19.1-1
- from 0, < 2:3.14.5-1+deb7u7
- from 0, < 2:3.26-1+debu8u1
- from 0, < 1.0.2b-1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | LOW3.7 | CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N |