Multiple use-after-free vulnerabilities in Privoxy before 3.0.22 allow remote attackers to have unspecified impact via vectors related to (1) the unmap function in list.c or (2) "two additional unconfirmed use-after-free complaints made by Coverity scan." NOTE: some of these details are obtained from third party information.

The remote Redhat Enterprise Linux 5 host has one or more packages installed that are affected by multiple vulnerabilities that have been acknowledged by the vendor but will not be patched.

  - privoxy: several use-after-free issues in list.c (CVE-2015-1031)

  - privoxy: invalid read via empty host header in client request (CVE-2016-1983)

  - Privoxy before 3.0.21 does not properly handle Proxy-Authenticate and Proxy-Authorization headers in the     client-server data stream, which makes it easier for remote HTTP servers to spoof the intended proxy     service via a 407 (aka Proxy Authentication Required) HTTP status code. (CVE-2013-2503)

Note that Nessus has not tested for these issues but has instead relied on the package manager's report that the package is installed.

Privoxy Developers reports :

Fixed a memory leak when rejecting client connections due to the socket limit being reached (CID 66382). This affected Privoxy 3.0.21 when compiled with IPv6 support (on most platforms this is the default).

Fixed an immediate-use-after-free bug (CID 66394) and two additional unconfirmed use-after-free complaints made by Coverity scan (CID 66391, CID 66376).

MITRE reports :

Privoxy before 3.0.22 allows remote attackers to cause a denial of service (file descriptor consumption) via unspecified vectors.

Several vulnerabilities have been fixed in privoxy, a privacy enhancing HTTP proxy :

CVE-2015-1031, CID66394 :

unmap(): Prevent use-after-free if the map only consists of one item.

CVE-2015-1031, CID66376 and CID66391 :

pcrs_execute(): Consistently set *result to NULL in case of errors.
Should make use-after-free in the caller less likely.

CVE-2015-1381 :

Fix multiple segmentation faults and memory leaks in the pcrs code.

CVE-2015-1382 :

Fix invalid read to prevent potential crashes.

We recommend that you upgrade your privoxy packages.

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

According to its self-identified version number, the Privoxy installed on the remote host is a version prior to 3.0.22. It is, therefore, affected by multiple vulnerabilities:

  - A denial of service vulnerability exists due to a     memory leak when client connections are rejected when     the socket limit has been reached. Note that this issue     only affects version 3.0.21 with IPv6 support, which is     enabled by default. (CVE-2015-1030)

  - Multiple unspecified use-after-free vulnerabilities     exist that could lead to arbitrary code execution.
    (CVE-2015-1031)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Multiple use-after-frees were discovered in Privoxy, a privacy-enhancing HTTP proxy.

ID	Name	Product	Family	Severity
199404	RHEL 5 : privoxy (Unpatched Vulnerability)	Nessus	Red Hat Local Security Checks	high
88150	FreeBSD : privoxy -- multiple vulnerabilities (89d4ed09-c3d7-11e5-b5fe-002590263bf5)	Nessus	FreeBSD Local Security Checks	high
82125	Debian DLA-142-1 : privoxy security update	Nessus	Debian Local Security Checks	high
81086	Privoxy < 3.0.22 Multiple Vulnerabilities	Nessus	Firewalls	high
80871	Debian DSA-3133-1 : privoxy - security update	Nessus	Debian Local Security Checks	high

Detections

Analytics

CVE-2015-1031

critical

Tenable Plugins

high

high

high

high

high