diff --git a/crypto/params_from_text.c b/crypto/params_from_text.c
index 38e0927195be0..15910298172e2 100644
--- a/crypto/params_from_text.c
+++ b/crypto/params_from_text.c
@@ -115,7 +115,13 @@ static int prepare_from_text(const OSSL_PARAM *paramdefs, const char *key,
         break;
     case OSSL_PARAM_OCTET_STRING:
         if (*ishex) {
-            *buf_n = strlen(value) >> 1;
+            size_t hexdigits = strlen(value);
+            if ((hexdigits % 2) != 0) {
+                /* We don't accept an odd number of hex digits */
+                ERR_raise(ERR_LIB_CRYPTO, CRYPTO_R_ODD_NUMBER_OF_DIGITS);
+                return 0;
+            }
+            *buf_n = hexdigits >> 1;
         } else {
             *buf_n = value_n;
         }
diff --git a/test/params_test.c b/test/params_test.c
index 614c8debb70ae..a4b17ddf8f657 100644
--- a/test/params_test.c
+++ b/test/params_test.c
@@ -15,6 +15,7 @@
 #include <string.h>
 #include <openssl/bn.h>
 #include <openssl/core.h>
+#include <openssl/err.h>
 #include <openssl/params.h>
 #include "internal/numbers.h"
 #include "internal/nelem.h"
@@ -558,6 +559,7 @@ static const OSSL_PARAM params_from_text[] = {
     /* Arbitrary size buffer.  Make sure the result fits in a long */
     OSSL_PARAM_DEFN("num", OSSL_PARAM_INTEGER, NULL, 0),
     OSSL_PARAM_DEFN("unum", OSSL_PARAM_UNSIGNED_INTEGER, NULL, 0),
+    OSSL_PARAM_DEFN("octets", OSSL_PARAM_OCTET_STRING, NULL, 0),
     OSSL_PARAM_END,
 };
 
@@ -655,14 +657,56 @@ static int check_int_from_text(const struct int_from_text_test_st a)
     return a.expected_res;
 }
 
+static int check_octetstr_from_hexstr(void)
+{
+    OSSL_PARAM param;
+    static const char *values[] = { "", "F", "FF", "FFF", "FFFF", NULL };
+    int i;
+    int errcnt = 0;
+
+    /* Test odd vs even number of hex digits */
+    for (i = 0; values[i] != NULL; i++) {
+        int expected = (strlen(values[i]) % 2) != 1;
+        int result;
+
+        ERR_clear_error();
+        memset(&param, 0, sizeof(param));
+        if (expected)
+            result =
+                TEST_true(OSSL_PARAM_allocate_from_text(&param,
+                                                        params_from_text,
+                                                        "hexoctets", values[i], 0,
+                                                        NULL));
+        else
+            result =
+                TEST_false(OSSL_PARAM_allocate_from_text(&param,
+                                                         params_from_text,
+                                                         "hexoctets", values[i], 0,
+                                                         NULL));
+        if (!result) {
+            TEST_error("unexpected OSSL_PARAM_allocate_from_text() %s for 'octets' \"%s\"",
+                       (expected ? "failure" : "success"), values[i]);
+            errcnt++;
+        }
+        OPENSSL_free(param.data);
+    }
+    return errcnt == 0;
+}
+
 static int test_allocate_from_text(int i)
 {
     return check_int_from_text(int_from_text_test_cases[i]);
 }
 
+static int test_more_allocate_from_text(void)
+{
+    return check_octetstr_from_hexstr();
+}
+
 int setup_tests(void)
 {
     ADD_ALL_TESTS(test_case, OSSL_NELEM(test_cases));
     ADD_ALL_TESTS(test_allocate_from_text, OSSL_NELEM(int_from_text_test_cases));
+    ADD_TEST(test_more_allocate_from_text);
     return 1;
 }