diff --git a/Documentation/MANPAGE-XRAY.md b/Documentation/MANPAGE-XRAY.md
index e8952f6..4d782a7 100644
--- a/Documentation/MANPAGE-XRAY.md
+++ b/Documentation/MANPAGE-XRAY.md
@@ -21,6 +21,10 @@ DESCRIPTION
 
 Available options are listed below.
 
+#### -aessiv
+Assume AES-SIV mode instead of AES-GCM when examining an encrypted file.
+Is not needed and has no effect in `-dumpmasterkey` mode.
+
 #### -dumpmasterkey
 Decrypts and shows the master key.
 
diff --git a/README.md b/README.md
index d4a4f4d..ec0fe05 100644
--- a/README.md
+++ b/README.md
@@ -176,6 +176,8 @@ v1.7, in progress (v1.7-beta1 released 2019-01-03)
 * Reverse mode: fix excluded, unaccessible files showing up in directory listings
   ([#285](https://github.com/rfjakob/gocryptfs/issues/285),
   [#286](https://github.com/rfjakob/gocryptfs/issues/286))
+* gocryptfs-xray: add `-aessiv` flag for correctly parsing AES-SIV format files
+  ([#299](https://github.com/rfjakob/gocryptfs/issues/299))
 
 v1.6.1, 2018-12-12
 * Fix "Operation not supported" chmod errors on Go 1.11