From https://bugzilla.redhat.com/show_bug.cgi?id=1275871: The SPNEGO mechanism currently replaces its context handle with the mechanism context handle upon establishment, under the assumption that most GSS functions are only called after context establishment. This assumption is incorrect, and can lead to aliasing violations for some programs. Maintain the SPNEGO context structure after context establishment and refer to it in all GSS methods. Add initiate and opened flags to the SPNEGO context structure for use in gss_inquire_context() prior to context establishment. CVE-2015-2695: In MIT krb5 1.5 and later, applications which call gss_inquire_context() on a partially-established SPNEGO context can cause the GSS-API library to read from a pointer using the wrong type, generally causing a process crash. This bug may go unnoticed, because the most common SPNEGO authentication scenario establishes the context after just one call to gss_accept_sec_context(). Java server applications using the native JGSS provider are vulnerable to this bug. A carefully crafted SPNEGO packet might allow the gss_inquire_context() call to succeed with attacker-determined results, but applications should not make access control decisions based on gss_inquire_context() results prior to context establishment. External References: https://github.com/krb5/krb5/commit/b51b33f2bc5d1497ddf5bd107f791c101695000d From https://bugzilla.redhat.com/show_bug.cgi?id=1275869: The IAKERB mechanism currently replaces its context handle with the krb5 mechanism handle upon establishment, under the assumption that most GSS functions are only called after context establishment. This assumption is incorrect, and can lead to aliasing violations for some programs. Maintain the IAKERB context structure after context establishment and add new IAKERB entry points to refer to it with that type. Add initiate and established flags to the IAKERB context structure for use in gss_inquire_context() prior to context establishment. CVE-2015-2696: In MIT krb5 1.9 and later, applications which call gss_inquire_context() on a partially-established IAKERB context can cause the GSS-API library to read from a pointer using the wrong type, generally causing a process crash. Java server applications using the native JGSS provider are vulnerable to this bug. A carefully crafted IAKERB packet might allow the gss_inquire_context() call to succeed with attacker-determined results, but applications should not make access control decisions based on gss_inquire_context() results prior to context establishment. External references: https://github.com/krb5/krb5/commit/e04f0283516e80d2f93366e0d479d13c9b5c8c2a From https://bugzilla.redhat.com/show_bug.cgi?id=1275863: In build_principal_va(), use k5memdup0() instead of strdup() to make a copy of the realm, to ensure that we allocate the correct number of bytes and do not read past the end of the input string. This bug affects krb5_build_principal(), krb5_build_principal_va(), and krb5_build_principal_alloc_va(). krb5_build_principal_ext() is not affected. CVE-2015-2697: In MIT krb5 1.7 and later, an authenticated attacker may be able to cause a KDC to crash using a TGS request with a large realm field beginning with a null byte. If the KDC attempts to find a referral to answer the request, it constructs a principal name for lookup using krb5_build_principal() with the requested realm. Due to a bug in this function, the null byte causes only one byte be allocated for the realm field of the constructed principal, far less than its length. Subsequent operations on the lookup principal may cause a read beyond the end of the mapped memory region, causing the KDC process to crash. External reference: https://github.com/krb5/krb5/commit/f0c094a1b745d91ef2f9a4eae2149aac026a5789 @maintainer(s): after the bump, in case we need to stabilize the package, please let us know if it is ready for the stabilization or not.
Arches, please test and mark stable =app-crypt/mit-krb5-1.13.2-r2 Target Keywords = alpha amd64 arm ~arm64 hppa ia64 ~mips ppc ppc64 ~s390 ~sh sparc x86
Stable for PPC64.
Stable for HPPA.
amd64 stable
x86 stable
Stable on alpha.
arm stable
ppc stable
sparc stable
ia64 stable
Arches and Maintainer(s), Thank you for your work. GLSA Vote: Yes New GLSA Request filed.
This issue was resolved and addressed in GLSA 201611-14 at https://security.gentoo.org/glsa/201611-14 by GLSA coordinator Aaron Bauman (b-man).
