CVE-2017-7805

moderate-risk
Published 2018-06-11

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.

Do I need to act?

~
3.2% chance of exploitation in next 30 days
EPSS score — moderate exploit probability
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
7
CVSS 7.5/10 High
NETWORK / LOW complexity

Affected Products (6)

Affected Vendors

Debian Mozilla

References (26)

http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
Third Party Advisory http://www.securityfocus.com/bid/101059
Third Party Advisory http://www.securitytracker.com/id/1039465
Third Party Advisory https://access.redhat.com/errata/RHSA-2017:2832
Issue Tracking https://bugzilla.mozilla.org/show_bug.cgi?id=1377618
Third Party Advisory https://lists.debian.org/debian-lts-announce/2017/11/msg00000.html
Third Party Advisory https://security.gentoo.org/glsa/201803-14
Third Party Advisory https://www.debian.org/security/2017/dsa-3987
Third Party Advisory https://www.debian.org/security/2017/dsa-3998
Third Party Advisory https://www.debian.org/security/2017/dsa-4014
Vendor Advisory https://www.mozilla.org/security/advisories/mfsa2017-21/
Vendor Advisory https://www.mozilla.org/security/advisories/mfsa2017-22/
Vendor Advisory https://www.mozilla.org/security/advisories/mfsa2017-23/
http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html
Third Party Advisory http://www.securityfocus.com/bid/101059
Third Party Advisory http://www.securitytracker.com/id/1039465
Third Party Advisory https://access.redhat.com/errata/RHSA-2017:2832
Issue Tracking https://bugzilla.mozilla.org/show_bug.cgi?id=1377618
Third Party Advisory https://lists.debian.org/debian-lts-announce/2017/11/msg00000.html
Third Party Advisory https://security.gentoo.org/glsa/201803-14
and 6 more references
45
/ 100
moderate-risk
Severity 26/34 · High
Exploitability 6/34 · Minimal
Exposure 13/34 · Low