Apply by doing:
       cd /usr/src
       patch -p0 < 005_httpd.patch

And then rebuild and install httpd:
       cd usr.sbin/httpd
       make -f Makefile.bsd-wrapper obj
       make -f Makefile.bsd-wrapper cleandir
       make -f Makefile.bsd-wrapper
       make -f Makefile.bsd-wrapper install

Index: usr.sbin/httpd/src/main/http_protocol.c
===================================================================
RCS file: /cvs/src/usr.sbin/httpd/src/main/http_protocol.c,v
retrieving revision 1.10
retrieving revision 1.10.2.1
diff -u -r1.10 -r1.10.2.1
--- usr.sbin/httpd/src/main/http_protocol.c     2002/03/29 02:08:06     1.10
+++ usr.sbin/httpd/src/main/http_protocol.c     2002/06/17 20:34:46     1.10.2.1
@@ -2028,21 +2028,34 @@
static long get_chunk_size(char *b)
{
    long chunksize = 0;
+    long chunkbits = sizeof(long) * 8;

-    while (ap_isxdigit(*b)) {
+    /* Skip leading zeros */
+    while (*b == '0') {
+        ++b;
+    }
+
+    while (ap_isxdigit(*b) && (chunkbits > 0)) {
        int xvalue = 0;

-       /* This works even on EBCDIC. */
-        if (*b >= '0' && *b <= '9')
+        if (*b >= '0' && *b <= '9') {
            xvalue = *b - '0';
-        else if (*b >= 'A' && *b <= 'F')
+        }
+        else if (*b >= 'A' && *b <= 'F') {
            xvalue = *b - 'A' + 0xa;
-        else if (*b >= 'a' && *b <= 'f')
+        }
+        else if (*b >= 'a' && *b <= 'f') {
            xvalue = *b - 'a' + 0xa;
+        }

        chunksize = (chunksize << 4) | xvalue;
+        chunkbits -= 4;
        ++b;
    }
+    if (ap_isxdigit(*b) && (chunkbits <= 0)) {
+        /* overflow */
+        return -1;
+    }

    return chunksize;
}
@@ -2126,6 +2139,10 @@
                return 0;
            }
            r->remaining = -1;  /* Indicate footers in-progress */
+        }
+        else if (len_to_read < 0) {
+            r->connection->keepalive = -1;
+            return -1;
        }
        else {
            r->remaining = len_to_read;