CVE-2017-7805
nss - security update
7.5
HIGH
CVSS 3.1
EPSS 3.2%
Description
During TLS 1.2 exchanges, handshake hashes are generated which point to a message buffer. This saved data is used for later messages but in some cases, the handshake transcript can exceed the space available in the current buffer, causing the allocation of a new buffer. This leaves a pointer pointing to the old, freed buffer, resulting in a use-after-free when handshake hashes are then calculated afterwards. This can result in a potentially exploitable crash. This vulnerability affects Firefox < 56, Firefox ESR < 52.4, and Thunderbird < 52.4.
How to fix CVE-2017-7805
To remediate CVE-2017-7805, upgrade the affected package to a fixed version below.
- —upgrade to 52.4.0esr-2 or later
- —upgrade to 2:3.33-1 or later
- —upgrade to 2:3.26-1+debu7u5 or later
- —upgrade to 2:3.26-1+debu8u3 or later
- —upgrade to 1:52.4.0-1 or later
Is CVE-2017-7805 being exploited?
Low — EPSS is 3.2%, meaning exploitation activity has not been observed at scale.
Affected packages (5)
- from 0, < 52.4.0esr-2
- from 0, < 2:3.33-1
- from 0, < 2:3.26-1+debu7u5
- from 0, < 2:3.26-1+debu8u3
- from 0, < 1:52.4.0-1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |