diff -up ./doc/sudoers.man.in.CVE-2019-19232 ./doc/sudoers.man.in
--- ./doc/sudoers.man.in.CVE-2019-19232 2019-10-28 13:28:52.000000000 +0100
+++ ./doc/sudoers.man.in 2020-01-14 15:34:46.908027286 +0100
@@ -2942,6 +2942,23 @@ This flag is
\fIoff\fR
by default.
.TP 18n
+runas_allow_unknown_id
+If enabled, allow matching of runas user and group IDs that are
+not present in the password or group databases.
+In addition to explicitly matching unknown user or group IDs in a
+\fRRunas_List\fR,
+this option also allows the
+\fBALL\fR
+alias to match unknown IDs.
+This flag is
+\fIoff\fR
+by default.
+.sp
+This setting is only supported by version 1.8.29 or higher.
+Older versions of
+\fBsudo\fR
+always allowed matching of unknown user and group IDs.
+.TP 18n
runaspw
If set,
\fBsudo\fR
diff -up ./doc/sudoers.mdoc.in.CVE-2019-19232 ./doc/sudoers.mdoc.in
--- ./doc/sudoers.mdoc.in.CVE-2019-19232 2019-10-28 13:28:52.000000000 +0100
+++ ./doc/sudoers.mdoc.in 2020-01-14 15:34:46.908027286 +0100
@@ -2768,6 +2768,22 @@ when running a command or editing a file
This flag is
.Em off
by default.
+.It runas_allow_unknown_id
+If enabled, allow matching of runas user and group IDs that are
+not present in the password or group databases.
+In addition to explicitly matching unknown user or group IDs in a
+.Li Runas_List ,
+this option also allows the
+.Sy ALL
+alias to match unknown IDs.
+This flag is
+.Em off
+by default.
+.Pp
+This setting is only supported by version 1.8.29 or higher.
+Older versions of
+.Nm sudo
+always allowed matching of unknown user and group IDs.
.It runaspw
If set,
.Nm sudo
diff -up ./plugins/sudoers/defaults.c.CVE-2019-19232 ./plugins/sudoers/defaults.c
--- ./plugins/sudoers/defaults.c.CVE-2019-19232 2020-01-14 15:34:46.902027246 +0100
+++ ./plugins/sudoers/defaults.c 2020-01-14 15:34:46.909027293 +0100
@@ -581,6 +581,7 @@ init_defaults(void)
def_fdexec = digest_only;
def_log_allowed = true;
def_log_denied = true;
+ def_runas_allow_unknown_id = false;
/* Syslog options need special care since they both strings and ints */
#if (LOGGING & SLOG_SYSLOG)
diff -up ./plugins/sudoers/def_data.c.CVE-2019-19232 ./plugins/sudoers/def_data.c
--- ./plugins/sudoers/def_data.c.CVE-2019-19232 2020-01-14 15:34:46.908027286 +0100
+++ ./plugins/sudoers/def_data.c 2020-01-14 15:40:19.441555509 +0100
@@ -514,6 +514,10 @@ struct sudo_defs_types sudo_defs_table[]
N_("Don't fork and wait for the command to finish, just exec it"),
NULL,
}, {
+ "runas_allow_unknown_id", T_FLAG,
+ N_("Allow the use of unknown runas user and/or group ID"),
+ NULL,
+ }, {
NULL, 0, NULL
}
};
diff -up ./plugins/sudoers/def_data.h.CVE-2019-19232 ./plugins/sudoers/def_data.h
--- ./plugins/sudoers/def_data.h.CVE-2019-19232 2020-01-14 15:34:46.909027293 +0100
+++ ./plugins/sudoers/def_data.h 2020-01-14 15:41:33.658012401 +0100
@@ -236,6 +236,8 @@
#define def_legacy_group_processing (sudo_defs_table[I_LEGACY_GROUP_PROCESSING].sd_un.flag)
#define I_CMND_NO_WAIT 118
#define def_cmnd_no_wait (sudo_defs_table[I_CMND_NO_WAIT].sd_un.flag)
+#define I_RUNAS_ALLOW_UNKNOWN_ID 119
+#define def_runas_allow_unknown_id (sudo_defs_table[I_RUNAS_ALLOW_UNKNOWN_ID].sd_un.flag)
enum def_tuple {
never,
diff -up ./plugins/sudoers/def_data.in.CVE-2019-19232 ./plugins/sudoers/def_data.in
--- ./plugins/sudoers/def_data.in.CVE-2019-19232 2020-01-14 15:34:46.909027293 +0100
+++ ./plugins/sudoers/def_data.in 2020-01-14 15:42:42.176481484 +0100
@@ -372,3 +372,6 @@ legacy_group_processing
cmnd_no_wait
T_FLAG
"Don't fork and wait for the command to finish, just exec it"
+runas_allow_unknown_id
+ T_FLAG
+ "Allow the use of unknown runas user and/or group ID"
diff -up ./plugins/sudoers/sudoers.c.CVE-2019-19232 ./plugins/sudoers/sudoers.c
--- ./plugins/sudoers/sudoers.c.CVE-2019-19232 2020-01-14 15:34:46.905027266 +0100
+++ ./plugins/sudoers/sudoers.c 2020-01-14 15:34:46.910027299 +0100
@@ -105,6 +105,8 @@ static char *prev_user;
static char *runas_user;
static char *runas_group;
static struct sudo_nss_list *snl;
+static bool unknown_runas_uid;
+static bool unknown_runas_gid;
#ifdef __linux__
static struct rlimit nproclimit;
@@ -354,6 +356,22 @@ sudoers_policy_main(int argc, char * con
}
}
+ /* Defer uid/gid checks until after defaults have been updated. */
+ if (unknown_runas_uid && !def_runas_allow_unknown_id) {
+ audit_failure(NewArgc, NewArgv, N_("unknown user: %s"),
+ runas_pw->pw_name);
+ sudo_warnx(U_("unknown user: %s"), runas_pw->pw_name);
+ goto done;
+ }
+ if (runas_gr != NULL) {
+ if (unknown_runas_gid && !def_runas_allow_unknown_id) {
+ audit_failure(NewArgc, NewArgv, N_("unknown group: %s"),
+ runas_gr->gr_name);
+ sudo_warnx(U_("unknown group: %s"), runas_gr->gr_name);
+ goto done;
+ }
+ }
+
/*
* Look up the timestamp dir owner if one is specified.
*/
@@ -1167,12 +1185,15 @@ set_runaspw(const char *user, bool quiet
struct passwd *pw = NULL;
debug_decl(set_runaspw, SUDOERS_DEBUG_PLUGIN)
+ unknown_runas_uid = false;
if (*user == '#') {
const char *errstr;
uid_t uid = sudo_strtoid(user + 1, &errstr);
if (errstr == NULL) {
- if ((pw = sudo_getpwuid(uid)) == NULL)
+ if ((pw = sudo_getpwuid(uid)) == NULL) {
+ unknown_runas_uid = true;
pw = sudo_fakepwnam(user, user_gid);
+ }
}
}
if (pw == NULL) {
@@ -1198,12 +1219,15 @@ set_runasgr(const char *group, bool quie
struct group *gr = NULL;
debug_decl(set_runasgr, SUDOERS_DEBUG_PLUGIN)
+ unknown_runas_gid = false;
if (*group == '#') {
const char *errstr;
gid_t gid = sudo_strtoid(group + 1, &errstr);
if (errstr == NULL) {
- if ((gr = sudo_getgrgid(gid)) == NULL)
+ if ((gr = sudo_getgrgid(gid)) == NULL) {
+ unknown_runas_gid = true;
gr = sudo_fakegrnam(group);
+ }
}
}
if (gr == NULL) {