It was discovered that libXdmcp before 1.1.2 including used weak entropy to generate session keys. On a multi-user system using xdmcp, a local attacker could potentially use information available from the process list to brute force the key, allowing them to hijack other users' sessions.

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

  - libXdmcp: weak entropy usage for session keys (CVE-2017-2625)

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

The remote Redhat Enterprise Linux 6 host has one or more packages installed that are affected by a vulnerability that has been acknowledged by the vendor but will not be patched.

  - libXdmcp: weak entropy usage for session keys (CVE-2017-2625)

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

The remote Ubuntu 16.04 ESM host has packages installed that are affected by a vulnerability as referenced in the USN-5690-1 advisory.

    It was discovered that libXdmcp was generating weak session keys. A local attacker could possibly use this     issue to perform a brute force attack and obtain another user's key.

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

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

According to the version of the libXdmcp package installed, the EulerOS Virtualization for ARM 64 installation on the remote host is affected by the following vulnerability :

  - It was discovered that libXdmcp used weak entropy to     generate session keys. On a multi-user system using     xdmcp, a local attacker could potentially use     information available from the process list to brute     force the key, allowing them to hijack other users'     sessions.(CVE-2017-2625)

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

It has been found, that libxdmcp, an X11 Display Manager Control Protocol library, uses weak entropy to generate keys.

Using arc4random_buf() from libbsd should avoid this flaw.

For Debian 8 'Jessie', this problem has been fixed in version 1:1.1.1-1+deb8u1.

We recommend that you upgrade your libxdmcp 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.

The freedesktop and x.org project reports :

It was discovered that libXdmcp before 1.1.3 used weak entropy to generate session keys on platforms without arc4random_buf() but with getentropy(). On a multi-user system using xdmcp, a local attacker could potentially use information available from the process list to brute force the key, allowing them to hijack other users' sessions.

Please note, that since FreeBSD provides arc4random_buf(), it is unknown if FreeBSD is affected by this vulnerability

This update for libXdmcp fixes the following issues :

  - CVE-2017-2625: The generation of session key in XDM     using libXdmcp might have used weak entropy, making the     session keys predictable (bsc#1025046)

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

According to the versions of the libXpm, libXdmcp, libICE packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :

  - An integer overflow flaw leading to a heap-based buffer     overflow was found in libXpm. An attacker could use     this flaw to crash an application using libXpm via a     specially crafted XPM file. (CVE-2016-10164)

  - It was discovered that libXdmcp used weak entropy to     generate session keys. On a multi-user system using     xdmcp, a local attacker could potentially use     information available from the process list to brute     force the key, allowing them to hijack other users'     sessions. (CVE-2017-2625)

  - It was discovered that libICE used a weak entropy to     generate keys. A local attacker could potentially use     this flaw for session hijacking using the information     available from the process list. (CVE-2017-2626)

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

An update is now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

The X11 (Xorg) libraries provide library routines that are used within all X Window applications.

The following packages have been upgraded to a later upstream version:
libX11 (1.6.5), libXaw (1.0.13), libXdmcp (1.1.2), libXfixes (5.0.3), libXfont (1.5.2), libXi (1.7.9), libXpm (3.5.12), libXrandr (1.5.1), libXrender (0.9.10), libXt (1.1.5), libXtst (1.2.3), libXv (1.0.11), libXvMC (1.0.10), libXxf86vm (1.1.4), libdrm (2.4.74), libepoxy (1.3.1), libevdev (1.5.6), libfontenc (1.1.3), libvdpau (1.1.1), libwacom (0.24), libxcb (1.12), libxkbfile (1.0.9), mesa (17.0.1), mesa-private-llvm (3.9.1), xcb-proto (1.12), xkeyboard-config (2.20), xorg-x11-proto-devel (7.7). (BZ#1401667, BZ#1401668, BZ#1401669, BZ#1401670, BZ#1401671, BZ#1401672, BZ#1401673, BZ#1401675, BZ# 1401676, BZ#1401677, BZ#1401678, BZ#1401679, BZ#1401680, BZ#1401681, BZ# 1401682, BZ#1401683, BZ#1401685, BZ#1401690, BZ#1401752, BZ#1401753, BZ# 1401754, BZ#1402560, BZ#1410477, BZ#1411390, BZ#1411392, BZ#1411393, BZ# 1411452, BZ#1420224)

Security Fix(es) :

* An integer overflow flaw leading to a heap-based buffer overflow was found in libXpm. An attacker could use this flaw to crash an application using libXpm via a specially crafted XPM file.
(CVE-2016-10164)

* It was discovered that libXdmcp used weak entropy to generate session keys. On a multi-user system using xdmcp, a local attacker could potentially use information available from the process list to brute force the key, allowing them to hijack other users' sessions.
(CVE-2017-2625)

* It was discovered that libICE used a weak entropy to generate keys.
A local attacker could potentially use this flaw for session hijacking using the information available from the process list. (CVE-2017-2626)

Red Hat would like to thank Eric Sesterhenn (X41 D-Sec GmbH) for reporting CVE-2017-2625 and CVE-2017-2626.

Additional Changes :

For detailed information on changes in this release, see the Red Hat Enterprise Linux 7.4 Release Notes linked from the References section.

The following packages have been upgraded to a later upstream version:
libX11 (1.6.5), libXaw (1.0.13), libXdmcp (1.1.2), libXfixes (5.0.3), libXfont (1.5.2), libXi (1.7.9), libXpm (3.5.12), libXrandr (1.5.1), libXrender (0.9.10), libXt (1.1.5), libXtst (1.2.3), libXv (1.0.11), libXvMC (1.0.10), libXxf86vm (1.1.4), libdrm (2.4.74), libepoxy (1.3.1), libevdev (1.5.6), libfontenc (1.1.3), libvdpau (1.1.1), libwacom (0.24), libxcb (1.12), libxkbfile (1.0.9), mesa (17.0.1), mesa-private-llvm (3.9.1), xcb-proto (1.12), xkeyboard-config (2.20), xorg-x11-proto-devel (7.7).

Security Fix(es) :

  - An integer overflow flaw leading to a heap-based buffer     overflow was found in libXpm. An attacker could use this     flaw to crash an application using libXpm via a     specially crafted XPM file. (CVE-2016-10164)

  - It was discovered that libXdmcp used weak entropy to     generate session keys. On a multi-user system using     xdmcp, a local attacker could potentially use     information available from the process list to brute     force the key, allowing them to hijack other users'     sessions. (CVE-2017-2625)

  - It was discovered that libICE used a weak entropy to     generate keys. A local attacker could potentially use     this flaw for session hijacking using the information     available from the process list. (CVE-2017-2626)

The remote Oracle Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2017-1865 advisory.

    - Use libbsd for randoms (CVE-2017-2626, rhbz#1427715)
    - Use libbsd for randoms (CVE-2017-2625, rhbz#1427716)
    - fixes CVE-2016-5407
    - fixes CVE-2016-7953

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

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

This update for xorg-x11-libXdmcp fixes the following issues :

  - CVE-2017-2625: The generation of session key in XDM     using libXdmcp might have used weak entropy, making the     session keys predictable (bsc#1025046)

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

Security fix for CVE-2017-2625

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

This update for libXdmcp fixes the following issues :

  - CVE-2017-2625: The generation of session key in XDM     using libXdmcp might have used weak entropy, making the     session keys predictable (boo#1025046)

The remote host is affected by the vulnerability described in GLSA-201704-03 (X.Org: Multiple vulnerabilities)

    Multiple vulnerabilities have been discovered in X.Org server and       libraries. Please review the CVE identifiers referenced below for       details.
  Impact :

    A local or remote users can utilize the vulnerabilities to attach to the       X.Org session as a user and execute arbitrary code.
  Workaround :

    There is no known workaround at this time.

ID	Name	Product	Family	Severity
199107	RHEL 5 : libxdmcp (Unpatched Vulnerability)	Nessus	Red Hat Local Security Checks	medium
198998	RHEL 6 : libxdmcp (Unpatched Vulnerability)	Nessus	Red Hat Local Security Checks	medium
166261	Ubuntu 16.04 ESM : libXdmcp vulnerability (USN-5690-1)	Nessus	Ubuntu Local Security Checks	medium
140982	EulerOS Virtualization for ARM 64 3.0.6.0 : libXdmcp (EulerOS-SA-2020-2034)	Nessus	Huawei Local Security Checks	medium
131291	Debian DLA-2006-1 : libxdmcp security update	Nessus	Debian Local Security Checks	medium
122987	FreeBSD : libXdmcp -- insufficient entropy generating session keys (1b6a10e9-4b7b-11e9-9e89-54e1ad3d6335)	Nessus	FreeBSD Local Security Checks	medium
106579	SUSE SLED12 / SLES12 Security Update : libXdmcp (SUSE-SU-2018:0338-1)	Nessus	SuSE Local Security Checks	medium
103070	EulerOS 2.0 SP2 : libXpm, libXdmcp, libICE (EulerOS-SA-2017-1212)	Nessus	Huawei Local Security Checks	critical
103069	EulerOS 2.0 SP1 : libXpm, libXdmcp, libICE (EulerOS-SA-2017-1211)	Nessus	Huawei Local Security Checks	critical
102740	CentOS 7 : libICE / libX11 / libXaw / libXcursor / libXdmcp / libXfixes / libXfont / libXfont2 / etc (CESA-2017:1865)	Nessus	CentOS Local Security Checks	critical
102636	Scientific Linux Security Update : X.org X11 libraries on SL7.x x86_64 (20170801)	Nessus	Scientific Linux Local Security Checks	critical
102340	Oracle Linux 7 : X.org / X11 / libraries (ELSA-2017-1865)	Nessus	Oracle Linux Local Security Checks	critical
102147	RHEL 7 : X.org X11 libraries (RHSA-2017:1865)	Nessus	Red Hat Local Security Checks	critical
101767	SUSE SLES11 Security Update : xorg-x11-libXdmcp (SUSE-SU-2017:1868-1)	Nessus	SuSE Local Security Checks	medium
101766	SUSE SLED12 / SLES12 Security Update : libXdmcp (SUSE-SU-2017:1862-1)	Nessus	SuSE Local Security Checks	medium
101569	Fedora 26 : libXdmcp (2017-09f65e5e00)	Nessus	Fedora Local Security Checks	medium
101286	openSUSE Security Update : libXdmcp (openSUSE-2017-789)	Nessus	SuSE Local Security Checks	medium
99276	GLSA-201704-03 : X.Org: Multiple vulnerabilities	Nessus	Gentoo Local Security Checks	critical
97538	Fedora 24 : libXdmcp (2017-bcb1999e65)	Nessus	Fedora Local Security Checks	medium
97502	Fedora 25 : libXdmcp (2017-9a9328c159)	Nessus	Fedora Local Security Checks	medium

Detections

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CVE-2017-2625

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Tenable Plugins

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