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| author | Greg Hudson <ghudson@mit.edu> | 2023-06-21 10:57:39 -0400 |
|---|---|---|
| committer | Greg Hudson <ghudson@mit.edu> | 2023-07-05 14:13:59 -0400 |
| commit | ef08b09c9459551aabbe7924fb176f1583053cdd (patch) | |
| tree | a97ab7ff78f1c1ae69f026e8dd0286a10828326f | |
| parent | 509d8db922e9ad6f108883838473b6178f89874a (diff) | |
| download | krb5-ef08b09c9459551aabbe7924fb176f1583053cdd.zip krb5-ef08b09c9459551aabbe7924fb176f1583053cdd.tar.gz krb5-ef08b09c9459551aabbe7924fb176f1583053cdd.tar.bz2 | |
Ensure array count consistency in kadm5 RPC
In _xdr_kadm5_principal_ent_rec(), ensure that n_key_data matches the
key_data array count when decoding. Otherwise when the structure is
later freed, xdr_array() could iterate over the wrong number of
elements, either leaking some memory or freeing uninitialized
pointers. Reported by Robert Morris.
CVE-2023-36054:
An authenticated attacker can cause a kadmind process to crash by
freeing uninitialized pointers. Remote code execution is unlikely.
An attacker with control of a kadmin server can cause a kadmin client
to crash by freeing uninitialized pointers.
ticket: 9099 (new)
tags: pullup
target_version: 1.21-next
target_version: 1.20-next
| -rw-r--r-- | src/lib/kadm5/kadm_rpc_xdr.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/src/lib/kadm5/kadm_rpc_xdr.c b/src/lib/kadm5/kadm_rpc_xdr.c index 0411c3f..287cae7 100644 --- a/src/lib/kadm5/kadm_rpc_xdr.c +++ b/src/lib/kadm5/kadm_rpc_xdr.c @@ -390,6 +390,7 @@ _xdr_kadm5_principal_ent_rec(XDR *xdrs, kadm5_principal_ent_rec *objp, int v) { unsigned int n; + bool_t r; if (!xdr_krb5_principal(xdrs, &objp->principal)) { return (FALSE); @@ -443,6 +444,9 @@ _xdr_kadm5_principal_ent_rec(XDR *xdrs, kadm5_principal_ent_rec *objp, if (!xdr_krb5_int16(xdrs, &objp->n_key_data)) { return (FALSE); } + if (xdrs->x_op == XDR_DECODE && objp->n_key_data < 0) { + return (FALSE); + } if (!xdr_krb5_int16(xdrs, &objp->n_tl_data)) { return (FALSE); } @@ -451,9 +455,10 @@ _xdr_kadm5_principal_ent_rec(XDR *xdrs, kadm5_principal_ent_rec *objp, return FALSE; } n = objp->n_key_data; - if (!xdr_array(xdrs, (caddr_t *) &objp->key_data, - &n, ~0, sizeof(krb5_key_data), - xdr_krb5_key_data_nocontents)) { + r = xdr_array(xdrs, (caddr_t *) &objp->key_data, &n, objp->n_key_data, + sizeof(krb5_key_data), xdr_krb5_key_data_nocontents); + objp->n_key_data = n; + if (!r) { return (FALSE); } |