From 9062b98319fa8a386da846fbc19a053dd6fc1aee Mon Sep 17 00:00:00 2001
From: Eric Blankenhorn <eric@wolfssl.com>
Date: Thu, 5 Mar 2026 15:25:29 -0600
Subject: [PATCH] Fix f284 harden wc_FreeRsaKey

---
 wolfcrypt/src/rsa.c | 28 +++++++++-------------------
 1 file changed, 9 insertions(+), 19 deletions(-)

diff --git a/wolfcrypt/src/rsa.c b/wolfcrypt/src/rsa.c
index 8d1fb10385..ab40a6efa9 100644
--- a/wolfcrypt/src/rsa.c
+++ b/wolfcrypt/src/rsa.c
@@ -564,27 +564,17 @@ int wc_FreeRsaKey(RsaKey* key)
 #endif
 
 #ifndef WOLFSSL_RSA_PUBLIC_ONLY
-    if (key->type == RSA_PRIVATE) {
+    /* Always forcezero private key fields, since they may contain residual
+     * sensitive data even when key->type is not RSA_PRIVATE (e.g., after a
+     * partial key decode failure). */
 #if defined(WOLFSSL_KEY_GEN) || defined(OPENSSL_EXTRA) || !defined(RSA_LOW_MEM)
-        mp_forcezero(&key->u);
-        mp_forcezero(&key->dQ);
-        mp_forcezero(&key->dP);
+    mp_forcezero(&key->u);
+    mp_forcezero(&key->dQ);
+    mp_forcezero(&key->dP);
 #endif
-        mp_forcezero(&key->q);
-        mp_forcezero(&key->p);
-        mp_forcezero(&key->d);
-    }
-    else {
-        /* private part */
-#if defined(WOLFSSL_KEY_GEN) || defined(OPENSSL_EXTRA) || !defined(RSA_LOW_MEM)
-        mp_clear(&key->u);
-        mp_clear(&key->dQ);
-        mp_clear(&key->dP);
-#endif
-        mp_clear(&key->q);
-        mp_clear(&key->p);
-        mp_clear(&key->d);
-    }
+    mp_forcezero(&key->q);
+    mp_forcezero(&key->p);
+    mp_forcezero(&key->d);
 #endif /* WOLFSSL_RSA_PUBLIC_ONLY */
 
     /* public part */