CVE-2015-8960

CVE	CVE-2015-8960
State	PUBLISHED
Assigner	redhat
Source Priority	CVE Program / NVD first with legacy fallback
Published	2016-09-21 02:59:00 UTC
Updated	2026-05-06 22:30:45 UTC
Description	The TLS protocol 1.2 and earlier supports the rsa_fixed_dh, dss_fixed_dh, rsa_fixed_ecdh, and ecdsa_fixed_ecdh values for ClientCertificateType but does not directly document the ability to compute the master secret in certain situations with a client secret key and server public key but not a server secret key, which makes it easier for man-in-the-middle attackers to spoof TLS servers by leveraging knowledge of the secret key for an arbitrary installed client X.509 certificate, aka the "Key Compromise Impersonation (KCI)" issue.

Primary CVSS: v3.1 8.1 HIGH from [email protected]

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS: 0.003270000 probability, percentile 0.555760000 (date 2026-05-06)

Problem Types: CWE-295 | n/a

Version	Source	Type	Score	Severity	Vector
3.1	[email protected]	Primary	8.1	HIGH	`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`
2.0	[email protected]	Primary	6.8		`AV:N/AC:M/Au:N/C:P/I:P/A:P`

Attack Vector

Network

Attack Complexity

High

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Access Vector

Network

Access Complexity

Medium

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

Partial

AV:N/AC:M/Au:N/C:P/I:P/A:P

Type	Vendor	Product	Version	Update	Edition	Language
Application	Apple	Safari	-	All	All	All
Application	Google	Chrome	-	All	All	All
Application	Ietf	Transport Layer Security	All	All	All	All
Application	Microsoft	Internet Explorer	-	All	All	All
Application	Mozilla	Firefox	-	All	All	All
Application	Netapp	Clustered Data Ontap Antivirus Connector	-	All	All	All
Application	Netapp	Data Ontap Edge	-	All	All	All
Application	Netapp	Host Agent	-	All	All	All
Application	Netapp	Oncommand Shift	-	All	All	All
Application	Netapp	Plug-in For Symantec Netbackup	-	All	All	All
Application	Netapp	Smi-s Provider	-	All	All	All
Application	Netapp	Snapdrive	-	All	All	All
Application	Netapp	Snapdrive	-	All	All	All
Application	Netapp	Snapmanager	-	All	All	All
Application	Netapp	Snapmanager	-	All	All	All
Application	Netapp	Snapprotect	-	All	All	All
Application	Netapp	Snap Creator Framework	-	All	All	All
Application	Netapp	Solidfire Hci Management Node	-	All	All	All
Application	Netapp	System Setup	-	All	All	All
Application	Opera	Opera Browser	-	All	All	All

Source	Vendor	Product	Version	Platforms
CNA	Na	N/a	affected n/a	Not specified

Reference	Source	Link	Tags
Matthew Green on Twitter: "This attack is hilarious. Install a client cert in a browser, MITM any connection it makes to certain servers. https://t.co/A1O2bQTOiE"	af854a3a-2127-422b-91ae-364da2661108	twitter.com	Press/Media Coverage, Technical Description, Third Party Advisory
KCI Attacks against TLS	af854a3a-2127-422b-91ae-364da2661108	kcitls.org	Exploit, Technical Description
oss-security - Re: Possible CVE for TLS protocol issue	af854a3a-2127-422b-91ae-364da2661108	www.openwall.com	Mailing List, Technical Description, Third Party Advisory
CVE-2015-8960 TLS Vulnerability in NetApp Products \| NetApp Product Security	af854a3a-2127-422b-91ae-364da2661108	security.netapp.com	Third Party Advisory
www.usenix.org/system/files/conference/woot15/woot15-paper-hlauschek.pdf	af854a3a-2127-422b-91ae-364da2661108	www.usenix.org	Exploit, Mitigation, Technical Description
TLS CVE-2015-8960 Man in the Middle Security Bypass Vulnerability	af854a3a-2127-422b-91ae-364da2661108	www.securityfocus.com	Broken Link, Third Party Advisory, VDB Entry
CVE Program record	CVE.ORG	www.cve.org	canonical
NVD vulnerability detail	NVD	nvd.nist.gov	canonical, analysis

No vendor comments have been submitted for this CVE.

There are currently no legacy QID mappings associated with this CVE.