Mozilla Firefox < 37.0.1 HTTP/2 Alt-Svc Header SSL MitM

low Nessus Network Monitor Plugin ID 8743
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Synopsis

The remote host has a web browser installed that is vulnerable to a man-in-the-middle (MitM) attack.

Description

Versions of Mozilla Firefox earlier than 37.0.1 are affected by an error related to the HTTP/2 'Alt-Svc' header and SSL certificate verification, which allows man-in-the-middle (MitM) attacks. Specifically, this affects the script 'modules/libpref/init/all.js' as certificates are not properly validated when handling an Alt-Svc header in an HTTP/2 response. By spoofing the TLS/SSL server via a certificate that appears valid, an attacker with the ability to intercept network traffic (e.g. MiTM, DNS cache poisoning) can disclose and optionally manipulate transmitted data.

Solution

Upgrade to Firefox 37.0.1 or later.

See Also

https://www.mozilla.org/security/announce/2014/mfsa2015-44.html

Plugin Details

Severity: Low

ID: 8743

Family: Web Clients

Published: 4/29/2015

Updated: 3/6/2019

Dependencies: 9131

Nessus ID: 82583, 82582

Risk Information

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N

Temporal Vector: CVSS2#E:ND/RL:OF/RC:C

CVSS v3

Risk Factor: Low

Base Score: 3.7

Temporal Score: 3.6

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Temporal Vector: CVSS:3.0/E:X/RL:O/RC:C

Vulnerability Information

CPE: cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

Patch Publication Date: 3/31/2015

Vulnerability Publication Date: 3/31/2015

Reference Information

CVE: CVE-2015-0799

BID: 73905

IAVA: 2015-A-0069