diff --git a/third_party/README.rnp b/third_party/README.rnp
index 0a38bf6b51a..f906f45ed1e 100644
--- a/third_party/README.rnp
+++ b/third_party/README.rnp
@@ -29,9 +29,4 @@ is at rnp/moz.yaml.
     > mach vendor ./moz.yaml --patch-mode none
     # followed by
     > mach vendor ./moz.yaml --patch-mode only
-
-
-Build notes:
-
-
-
+   
diff --git a/third_party/patches/rnp/pr2145.patch b/third_party/patches/rnp/pr2145.patch
new file mode 100644
index 00000000000..0022d2fb8ac
--- /dev/null
+++ b/third_party/patches/rnp/pr2145.patch
@@ -0,0 +1,27 @@
+From d211911a54080b6dd551572c9a7cad5611bfa7bc Mon Sep 17 00:00:00 2001
+From: Rob Lemley <rob@thunderbird.net>
+Date: Wed, 8 Nov 2023 11:23:13 -0500
+Subject: [PATCH] Use typedef for Windows ssize_t. Fixes #2144.
+
+---
+ src/common/uniwin.h | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/common/uniwin.h b/src/common/uniwin.h
+index 095c325b..b7e2b52d 100644
+--- a/src/common/uniwin.h
++++ b/src/common/uniwin.h
+@@ -35,9 +35,9 @@
+ #include <direct.h> /* for _getcwd() and _chdir() */
+ 
+ #ifdef _WIN64
+-#define ssize_t __int64
++typedef __int64 ssize_t;
+ #else
+-#define ssize_t long
++typedef long ssize_t;
+ #endif
+ 
+ #define STDIN_FILENO 0
+-- 
+2.42.1
diff --git a/third_party/rnp/moz.yaml b/third_party/rnp/moz.yaml
index e2249767fca..bc5f39f6b7c 100644
--- a/third_party/rnp/moz.yaml
+++ b/third_party/rnp/moz.yaml
@@ -12,7 +12,7 @@ origin:
   url: "https://www.rnpgp.org/"
   license: BSD-2-Clause
 
-  release: v0.17.0 (2023-05-02T08:01:48Z).
+  release: v0.17.0 (2023-05-02T11:01:48+03:00).
 
   revision: v0.17.0
 
@@ -68,6 +68,7 @@ vendoring:
 
   patches:
     - ../patches/rnp/bug1843535_gcc13_missing_header.patch
+    - ../patches/rnp/pr2145.patch
 
   update-actions:
     - action: replace-in-file-regex
diff --git a/third_party/rnp/src/common/uniwin.h b/third_party/rnp/src/common/uniwin.h
index 095c325bcb9..b7e2b52d52b 100644
--- a/third_party/rnp/src/common/uniwin.h
+++ b/third_party/rnp/src/common/uniwin.h
@@ -35,9 +35,9 @@
 #include <direct.h> /* for _getcwd() and _chdir() */
 
 #ifdef _WIN64
-#define ssize_t __int64
+typedef __int64 ssize_t;
 #else
-#define ssize_t long
+typedef long ssize_t;
 #endif
 
 #define STDIN_FILENO 0