Double free vulnerability in MIT Kerberos 5 (aka krb5) allows attackers to have unspecified impact via vectors involving automatic deletion of security contexts on error.

An update of the krb5 package has been released.

The remote Redhat Enterprise Linux 6 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.

  - krb5: Automatic sec context deletion could lead to double-free (CVE-2017-11462)

  - The kadm5_randkey_principal_3 function in lib/kadm5/srv/svr_principal.c in kadmind in MIT Kerberos 5 (aka     krb5) before 1.13 sends old keys in a response to a -randkey -keepold request, which allows remote     authenticated users to forge tickets by leveraging administrative access. (CVE-2014-5351)

  - lib/gssapi/spnego/spnego_mech.c in MIT Kerberos 5 (aka krb5) before 1.14 relies on an inappropriate     context handle, which allows remote attackers to cause a denial of service (incorrect pointer read and     process crash) via a crafted SPNEGO packet that is mishandled during a gss_inquire_context call.
    (CVE-2015-2695)

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

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.

  - krb5: kadmind doubly frees partial deserialization results (MITKRB5-SA-2015-001) (CVE-2014-9421)

  - krb5: Automatic sec context deletion could lead to double-free (CVE-2017-11462)

  - The kadm5_randkey_principal_3 function in lib/kadm5/srv/svr_principal.c in kadmind in MIT Kerberos 5 (aka     krb5) before 1.13 sends old keys in a response to a -randkey -keepold request, which allows remote     authenticated users to forge tickets by leveraging administrative access. (CVE-2014-5351)

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

The remote Redhat Enterprise Linux 7 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.

  - krb5: Buffer overflow in get_matching_data() (CVE-2017-15088)

  - Kerberos: delegation constrain bypass in S4U2Proxy (CVE-2020-17049)

  - The kadm5_randkey_principal_3 function in lib/kadm5/srv/svr_principal.c in kadmind in MIT Kerberos 5 (aka     krb5) before 1.13 sends old keys in a response to a -randkey -keepold request, which allows remote     authenticated users to forge tickets by leveraging administrative access. (CVE-2014-5351)

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

This plugin has been deprecated as it does not adhere to established standards for this style of check.

According to the versions of the krb5 packages installed, the EulerOS Virtualization installation on the remote host is affected by the following vulnerabilities :

  - Double free vulnerability in MIT Kerberos 5 (aka krb5)     allows attackers to have unspecified impact via vectors     involving automatic deletion of security contexts on     error.(CVE-2017-11462)

  - A Reachable Assertion issue was discovered in the KDC     in MIT Kerberos 5 (aka krb5) before 1.17. If an     attacker can obtain a krbtgt ticket using an older     encryption type (single-DES, triple-DES, or RC4), the     attacker can crash the KDC by making an S4U2Self     request.(CVE-2018-20217)

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.

According to the versions of the krb5 packages installed, the EulerOS Virtualization for ARM 64 installation on the remote host is affected by the following vulnerabilities :

  - Double free vulnerability in MIT Kerberos 5 (aka krb5)     allows attackers to have unspecified impact via vectors     involving automatic deletion of security contexts on     error.(CVE-2017-11462)

  - A Reachable Assertion issue was discovered in the KDC     in MIT Kerberos 5 (aka krb5) before 1.17. If an     attacker can obtain a krbtgt ticket using an older     encryption type (single-DES, triple-DES, or RC4), the     attacker can crash the KDC by making an S4U2Self     request.(CVE-2018-20217)

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.

According to the version of the krb5 packages installed, the EulerOS installation on the remote host is affected by the following vulnerability :

  - Double free vulnerability in MIT Kerberos 5 (aka krb5)     allows attackers to have unspecified impact via vectors     involving automatic deletion of security contexts on     error.(CVE-2017-11462)

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.

This update for krb5 fixes several issues. This security issue was fixed :

  - CVE-2017-11462: Prevent automatic security context     deletion to prevent double-free (bsc#1056995).

  - CVE-2018-5729: NULL pointer dereference in kadmind or DN     container check bypass by supplying special crafted data     (bsc#1083926).

  - CVE-2018-5730: DN container check bypass by supplying     special crafted data (bsc#1083927).

The update package also includes non-security fixes. See advisory for details.

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.

- Prevent applications from accidentally implementing     CVE-2017-11462 (double free if sec_context is copied).

  - fc26+: Add ccselect hostrealm module for ccache     selection based on service hostname.

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.

MIT reports :

CVE-2017-11368 :

In MIT krb5 1.7 and later, an authenticated attacker can cause an assertion failure in krb5kdc by sending an invalid S4U2Self or S4U2Proxy request.

CVE-2017-11462 :

RFC 2744 permits a GSS-API implementation to delete an existing security context on a second or subsequent call to gss_init_sec_context() or gss_accept_sec_context() if the call results in an error. This API behavior has been found to be dangerous, leading to the possibility of memory errors in some callers. For safety, GSS-API implementations should instead preserve existing security contexts on error until the caller deletes them.

All versions of MIT krb5 prior to this change may delete acceptor contexts on error. Versions 1.13.4 through 1.13.7, 1.14.1 through 1.14.5, and 1.15 through 1.15.1 may also delete initiator contexts on error.

This update for krb5 fixes several issues.

This security issue was fixed :

  - CVE-2017-11462: Prevent automatic security context     deletion to prevent double-free (bsc#1056995)

These non-security issues were fixed :

  - Set 'rdns' and 'dns_canonicalize_hostname' to false in     krb5.conf in order to improve client security in     handling service principle names. (bsc#1054028)

  - Prevent kadmind.service startup failure caused by     absence of LDAP service. (bsc#903543)

  - Remove main package's dependency on systemd     (bsc#1032680)

This update was imported from the SUSE:SLE-12-SP2:Update update project.

This update for krb5 fixes several issues. This security issue was fixed :

  - CVE-2017-11462: Prevent automatic security context     deletion to prevent double-free (bsc#1056995)

The update package also includes non-security fixes. See advisory for details.

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.

ID	Name	Product	Family	Severity
202838	Photon OS 1.0: Krb5 PHSA-2017-0038	Nessus	PhotonOS Local Security Checks	critical
199166	RHEL 6 : krb5 (Unpatched Vulnerability)	Nessus	Red Hat Local Security Checks	critical
199152	RHEL 5 : krb5 (Unpatched Vulnerability)	Nessus	Red Hat Local Security Checks	critical
199136	RHEL 7 : krb5 (Unpatched Vulnerability)	Nessus	Red Hat Local Security Checks	critical
196489	RHEL 6 : krb5 (Unpatched Vulnerability) (deprecated)	Nessus	Red Hat Local Security Checks	critical
196450	RHEL 7 : krb5 (Unpatched Vulnerability) (deprecated)	Nessus	Red Hat Local Security Checks	critical
196428	RHEL 5 : krb5 (Unpatched Vulnerability) (deprecated)	Nessus	Red Hat Local Security Checks	critical
135629	EulerOS Virtualization 3.0.2.2 : krb5 (EulerOS-SA-2020-1467)	Nessus	Huawei Local Security Checks	critical
134481	EulerOS Virtualization for ARM 64 3.0.2.0 : krb5 (EulerOS-SA-2020-1192)	Nessus	Huawei Local Security Checks	critical
130871	EulerOS 2.0 SP5 : krb5 (EulerOS-SA-2019-2162)	Nessus	Huawei Local Security Checks	critical
129251	EulerOS 2.0 SP3 : krb5 (EulerOS-SA-2019-2058)	Nessus	Huawei Local Security Checks	critical
128900	EulerOS 2.0 SP2 : krb5 (EulerOS-SA-2019-1848)	Nessus	Huawei Local Security Checks	critical
108826	SUSE SLES11 Security Update : krb5 (SUSE-SU-2018:0859-1)	Nessus	SuSE Local Security Checks	critical
105909	Fedora 27 : krb5 (2017-7a22a80c7e)	Nessus	Fedora Local Security Checks	critical
103953	FreeBSD : krb5 -- Multiple vulnerabilities (3f3837cc-48fb-4414-aa46-5b1c23c9feae)	Nessus	FreeBSD Local Security Checks	critical
103799	openSUSE Security Update : krb5 (openSUSE-2017-1145)	Nessus	SuSE Local Security Checks	critical
103742	SUSE SLED12 / SLES12 Security Update : krb5 (SUSE-SU-2017:2659-1)	Nessus	SuSE Local Security Checks	critical
103544	Fedora 25 : krb5 (2017-56e23bc2b5)	Nessus	Fedora Local Security Checks	critical
103098	Fedora 26 : krb5 (2017-10c74147f9)	Nessus	Fedora Local Security Checks	critical

Detections

Analytics

CVE-2017-11462

critical

Tenable Plugins

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical

critical