2 files changed, 4 insertions, 1 deletions
diff --git a/NEWS b/NEWS
index 85fa1f29..a9ef33b6 100644
--- a/NEWS
+++ b/NEWS
@@ -124,6 +124,9 @@ fetchmail-6.4.0 (not yet released):
   or that #define OPENSSL_NO_SSL3 inside #include <openssl/ssl.h>
   Related to Debian Bug#775255. Fixes Debian Bug #804604.
 * Version report lists -SSLv3 on SSL-enabled no-ssl3 builds.
+* Fetchmail no longer adds a NUL byte to the username in GSSAPI authentication.
+  This was reported to break Kerberos-based authentication with Microsoft
+  Exchange 2013 by Greg Hudson.
 
 # KNOWN BUGS AND WORKAROUNDS
   (This section floats upwards through the NEWS file so it stays with the
diff --git a/gssapi.c b/gssapi.c
index c2c7d94f..31247e3b 100644
--- a/gssapi.c
+++ b/gssapi.c
@@ -269,7 +269,7 @@ cancelfail:
     memcpy(buf1, &buf_size, 4);
     buf1[0] = GSSAUTH_P_NONE;
     strlcpy(buf1+4, username, sizeof(buf1) - 4); /* server decides if princ is user */
-    request_buf.length = 4 + strlen(username) + 1;
+    request_buf.length = 4 + strlen(username);
     request_buf.value = buf1;
     maj_stat = gss_wrap(&min_stat, context, 0, GSS_C_QOP_DEFAULT, &request_buf,
         &cflags, &send_token);