1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
|
From 027421cbd2e6e628f5f959c74d722afadc477485 Mon Sep 17 00:00:00 2001
From: Tobias Brunner <tobias@strongswan.org>
Date: Tue, 11 Jul 2023 12:12:25 +0200
Subject: [PATCH] charon-tkm: Validate DH public key to fix potential buffer
overflow
Seems this was forgotten in the referenced commit and actually could lead
to a buffer overflow. Since charon-tkm is untrusted this isn't that
much of an issue but could at least be easily exploited for a DoS attack
as DH public values are set when handling IKE_SA_INIT requests.
Fixes: 0356089d0f94 ("diffie-hellman: Verify public DH values in backends")
Fixes: CVE-2023-41913
Upstream-Status: Backport [https://download.strongswan.org/security/CVE-2023-41913/strongswan-5.3.0-5.9.6_charon_tkm_dh_len.patch]
CVE: CVE-2023-41913
Signed-off-by: Vijay Anusuri <vanusuri@mvista.com>
---
src/charon-tkm/src/tkm/tkm_diffie_hellman.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/src/charon-tkm/src/tkm/tkm_diffie_hellman.c b/src/charon-tkm/src/tkm/tkm_diffie_hellman.c
index 2b2d103d03e9..6999ad360d7e 100644
--- a/src/charon-tkm/src/tkm/tkm_diffie_hellman.c
+++ b/src/charon-tkm/src/tkm/tkm_diffie_hellman.c
@@ -70,11 +70,16 @@ METHOD(key_exchange_t, get_shared_secret, bool,
return TRUE;
}
-
METHOD(diffie_hellman_t, set_other_public_value, bool,
private_tkm_diffie_hellman_t *this, chunk_t value)
{
dh_pubvalue_type othervalue;
+
+ if (!key_exchange_verify_pubkey(this->group, value) ||
+ value.len > sizeof(othervalue.data))
+ {
+ return FALSE;
+ }
othervalue.size = value.len;
memcpy(&othervalue.data, value.ptr, value.len);
--
2.34.1
|
