49 lines
1.5 KiB
Diff
49 lines
1.5 KiB
Diff
From df17a1224a3406f57477bcd372c61e04c0e5a5bb Mon Sep 17 00:00:00 2001
|
|
From: Greg Hudson <ghudson@mit.edu>
|
|
Date: Fri, 8 Jan 2016 12:45:25 -0500
|
|
Subject: [PATCH 1/3] Verify decoded kadmin C strings [CVE-2015-8629]
|
|
|
|
In xdr_nullstring(), check that the decoded string is terminated with
|
|
a zero byte and does not contain any internal zero bytes.
|
|
|
|
CVE-2015-8629:
|
|
|
|
In all versions of MIT krb5, an authenticated attacker can cause
|
|
kadmind to read beyond the end of allocated memory by sending a string
|
|
without a terminating zero byte. Information leakage may be possible
|
|
for an attacker with permission to modify the database.
|
|
|
|
CVSSv2 Vector: AV:N/AC:H/Au:S/C:P/I:N/A:N/E:POC/RL:OF/RC:C
|
|
|
|
ticket: 8341 (new)
|
|
target_version: 1.14-next
|
|
target_version: 1.13-next
|
|
tags: pullup
|
|
---
|
|
src/lib/kadm5/kadm_rpc_xdr.c | 9 ++++++++-
|
|
1 file changed, 8 insertions(+), 1 deletion(-)
|
|
|
|
diff --git a/src/lib/kadm5/kadm_rpc_xdr.c b/src/lib/kadm5/kadm_rpc_xdr.c
|
|
index 2bef858..ba67084 100644
|
|
--- a/src/lib/kadm5/kadm_rpc_xdr.c
|
|
+++ b/src/lib/kadm5/kadm_rpc_xdr.c
|
|
@@ -64,7 +64,14 @@ bool_t xdr_nullstring(XDR *xdrs, char **objp)
|
|
return FALSE;
|
|
}
|
|
}
|
|
- return (xdr_opaque(xdrs, *objp, size));
|
|
+ if (!xdr_opaque(xdrs, *objp, size))
|
|
+ return FALSE;
|
|
+ /* Check that the unmarshalled bytes are a C string. */
|
|
+ if ((*objp)[size - 1] != '\0')
|
|
+ return FALSE;
|
|
+ if (memchr(*objp, '\0', size - 1) != NULL)
|
|
+ return FALSE;
|
|
+ return TRUE;
|
|
|
|
case XDR_ENCODE:
|
|
if (size != 0)
|
|
--
|
|
2.7.0.rc3
|
|
|