1 files changed, 8 insertions, 3 deletions

diff --git a/src/lib/libcrypto/cms/cms_kari.c b/src/lib/libcrypto/cms/cms_kari.c
index c23da18058..a16f51a569 100644
--- a/src/lib/libcrypto/cms/cms_kari.c
+++ b/src/lib/libcrypto/cms/cms_kari.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: cms_kari.c,v 1.18 2025/05/10 05:54:38 tb Exp $ */
+/* $OpenBSD: cms_kari.c,v 1.19 2026/08/27 07:13:34 tb Exp $ */
 /*
  * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
  * project.
@@ -250,6 +250,7 @@ cms_kek_cipher(unsigned char **pout, size_t *poutlen, const unsigned char *in,
         size_t keklen;
         int rv = 0;
         unsigned char *out = NULL;
+        size_t outsize = 0;
         int outlen;
 
         keklen = EVP_CIPHER_CTX_key_length(kari->ctx);
@@ -264,7 +265,11 @@ cms_kek_cipher(unsigned char **pout, size_t *poutlen, const unsigned char *in,
         /* obtain output length of ciphered key */
         if (!EVP_CipherUpdate(kari->ctx, NULL, &outlen, in, inlen))
                 goto err;
-        out = malloc(outlen);
+
+        outsize = outlen;
+        if (outsize < inlen)
+                outsize = inlen;
+        out = malloc(outsize);
         if (out == NULL)
                 goto err;
         if (!EVP_CipherUpdate(kari->ctx, out, &outlen, in, inlen))
@@ -276,7 +281,7 @@ cms_kek_cipher(unsigned char **pout, size_t *poutlen, const unsigned char *in,
  err:
         explicit_bzero(kek, keklen);
         if (!rv)
-                free(out);
+                freezero(out, outsize);
         (void)EVP_CIPHER_CTX_reset(kari->ctx);
         /* FIXME: WHY IS kari->pctx freed here?  /RL */
         EVP_PKEY_CTX_free(kari->pctx);