diff --git a/semver.c b/semver.c
index 3b07e97..6bd24db 100644
--- a/semver.c
+++ b/semver.c
@@ -130,8 +130,12 @@ int parseGitRev(char *vp, GitRevision *git) {
 int parsePreRelease(PreRelease *pr, char *s) {
     PreReleaseTag tag;
     long          val = 0;
-    char         *vp;
+    char          v[50];
+    char         *vp = (char *)v;
+    ssize_t       len = strnlen(s, 52);
 
+    if (len > 50) return 1;
+    memcpy(s, vp, len);
     if (strncasecmp(s, "alpha", 5) == 0) {
         tag = Alpha;
         vp = s + 5;