File xrdp-CVE-2022-23482.patch of Package xrdp.29105
From 9b768e6eeed70b6e5a762cc60a7c4f2e9d33076d Mon Sep 17 00:00:00 2001
From: matt335672 <30179339+matt335672@users.noreply.github.com>
Date: Wed, 7 Dec 2022 11:05:46 +0000
Subject: [PATCH] CVE-2022-23482
Check minimum length of TS_UD_CS_CORE message
---
libxrdp/xrdp_sec.c | 25 ++++++++++++++++++++++++-
1 file changed, 24 insertions(+), 1 deletion(-)
diff --git a/libxrdp/xrdp_sec.c b/libxrdp/xrdp_sec.c
index 1d3b0061..ec622721 100644
--- a/libxrdp/xrdp_sec.c
+++ b/libxrdp/xrdp_sec.c
@@ -1570,13 +1570,31 @@ xrdp_sec_send_fastpath(struct xrdp_sec *self, struct stream *s)
static int APP_CC
xrdp_sec_process_mcs_data_CS_CORE(struct xrdp_sec* self, struct stream* s)
{
+#define CS_CORE_MIN_LENGTH \
+ (\
+ 4 + /* Version */ \
+ 2 + 2 + /* desktopWidth + desktopHeight */ \
+ 2 + 2 + /* colorDepth + SASSequence */ \
+ 4 + /* keyboardLayout */ \
+ 4 + 32 + /* clientBuild + clientName */ \
+ 4 + 4 + 4 + /* keyboardType + keyboardSubType + keyboardFunctionKey */ \
+ 64 + /* imeFileName */ \
+ 0)
+
+ int version;
int colorDepth;
int postBeta2ColorDepth;
int highColorDepth;
int supportedColorDepths;
int earlyCapabilityFlags;
- in_uint8s(s, 4); /* version */
+ /* TS_UD_CS_CORE required fields */
+ if (!s_check_rem_and_log(s, CS_CORE_MIN_LENGTH,
+ "Parsing [MS-RDPBCGR] TS_UD_CS_CORE"))
+ {
+ return 1;
+ }
+ in_uint32_le(s, version);
in_uint16_le(s, self->rdp_layer->client_info.width);
in_uint16_le(s, self->rdp_layer->client_info.height);
in_uint16_le(s, colorDepth);
@@ -1598,6 +1616,10 @@ xrdp_sec_process_mcs_data_CS_CORE(struct xrdp_sec* self, struct stream* s)
in_uint8s(s, 4); /* keyboardSubType */
in_uint8s(s, 4); /* keyboardFunctionKey */
in_uint8s(s, 64); /* imeFileName */
+ if (!s_check_rem(s, 2))
+ {
+ return 0;
+ }
in_uint16_le(s, postBeta2ColorDepth);
g_writeln("postBeta2ColorDepth 0x%4.4x (0xca00 4bpp 0xca01 8bpp "
"0xca02 15bpp 0xca03 16bpp 0xca04 24bpp)", postBeta2ColorDepth);
@@ -1707,6 +1729,7 @@ xrdp_sec_process_mcs_data_CS_CORE(struct xrdp_sec* self, struct stream* s)
in_uint8s(s, 2); /* reserved */
return 0;
+#undef CS_CORE_MIN_LENGTH
}
/*****************************************************************************/
--
2.40.1