squid/SOURCES/squid-5.5-CVE-2023-46847.patch
2023-11-02 16:48:44 +00:00

44 lines
1.7 KiB
Diff

From 052cf082b0faaef4eaaa4e94119d7a1437aac4a3 Mon Sep 17 00:00:00 2001
From: squidadm <squidadm@users.noreply.github.com>
Date: Wed, 18 Oct 2023 04:50:56 +1300
Subject: [PATCH] Fix stack buffer overflow when parsing Digest Authorization
(#1517)
The bug was discovered and detailed by Joshua Rogers at
https://megamansec.github.io/Squid-Security-Audit/digest-overflow.html
where it was filed as "Stack Buffer Overflow in Digest Authentication".
---------
Co-authored-by: Alex Bason <nonsleepr@gmail.com>
Co-authored-by: Amos Jeffries <yadij@users.noreply.github.com>
---
src/auth/digest/Config.cc | 10 +++++++---
1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/src/auth/digest/Config.cc b/src/auth/digest/Config.cc
index d42831a55..be9f3c433 100644
--- a/src/auth/digest/Config.cc
+++ b/src/auth/digest/Config.cc
@@ -844,11 +844,15 @@ Auth::Digest::Config::decode(char const *proxy_auth, const HttpRequest *request,
break;
case DIGEST_NC:
- if (value.size() != 8) {
+ if (value.size() == 8) {
+ // for historical reasons, the nc value MUST be exactly 8 bytes
+ static_assert(sizeof(digest_request->nc) == 8 + 1, "bad nc buffer size");
+ xstrncpy(digest_request->nc, value.rawBuf(), value.size() + 1);
+ debugs(29, 9, "Found noncecount '" << digest_request->nc << "'");
+ } else {
debugs(29, 9, "Invalid nc '" << value << "' in '" << temp << "'");
+ digest_request->nc[0] = 0;
}
- xstrncpy(digest_request->nc, value.rawBuf(), value.size() + 1);
- debugs(29, 9, "Found noncecount '" << digest_request->nc << "'");
break;
case DIGEST_CNONCE:
--
2.25.1