Fix potential integer overflow parsing DER CRL
This patch prevents a potential signed integer overflow during the
CRL version verification checks.
diff --git a/ChangeLog b/ChangeLog
index 081bcf1..e50604d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -13,6 +13,10 @@
Found by redplait #590
* Add MPI_CHK to check for error value of mpi_fill_random.
Backported from a report and fix suggestion by guidovranken in #740
+ * Fix a potential integer overflow in the version verification for DER
+ encoded X509 CRLs. The overflow would enable maliciously constructed CRLs
+ to bypass the version verification check. Found by Peng Li/Yueh-Hsun Lin,
+ KNOX Security, Samsung Research America
= mbed TLS 1.3.20 branch released 2017-06-21