Daniel Wachdorf reported two problems in the MIT krb5 distribution used for network authentication. First, the KDC program from the krb5-kdc package can corrupt the heap by trying to free memory which has already been freed on receipt of a certain TCP connection. This vulnerability can cause the KDC to crash, leading to a denial of service. [CAN-2005-1174] Second, under certain rare circumstances this type of request can lead to a buffer overflow and remote code execution. [CAN-2005-1175] Additionally, Magnus Hagander reported another problem in which the krb5_recvauth function can in certain circumstances free previously freed memory, potentially leading to the execution of remote code. [CAN-2005-1689] All of these vulnerabilities are believed difficult to exploit, and no exploits have yet been discovered. For the old stable distribution (woody), these problems have been fixed in version 1.2.4-5woody10. Note that woody's KDC does not have TCP support and is not vulnerable to CAN-2005-1174. For the stable distribution (sarge), these problems have been fixed in version 1.3.6-2sarge2. For the unstable distribution (sid), these problems have been fixed in version 1.3.6-4. We recommend that you upgrade your krb5 package.
Daniel Wachdorf reported two problems in the MIT krb5 distribution used for network authentication. First, the KDC program from the krb5-kdc package can corrupt the heap by trying to free memory which has already been freed on receipt of a certain TCP connection. This vulnerability can cause the KDC to crash, leading to a denial of service. [CAN-2005-1174] Second, under certain rare circumstances this type of request can lead to a buffer overflow and remote code execution. [CAN-2005-1175]
Additionally, Magnus Hagander reported another problem in which the krb5_recvauth function can in certain circumstances free previously freed memory, potentially leading to the execution of remote code. [CAN-2005-1689]
All of these vulnerabilities are believed difficult to exploit, and no exploits have yet been discovered.
For the old stable distribution (woody), these problems have been fixed in version 1.2.4-5woody10. Note that woody's KDC does not have TCP support and is not vulnerable to CAN-2005-1174.
For the stable distribution (sarge), these problems have been fixed in version 1.3.6-2sarge2.
For the unstable distribution (sid), these problems have been fixed in version 1.3.6-4.
We recommend that you upgrade your krb5 package.
MD5 checksums of the listed files are available in the original advisory.
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