diff --git a/UPGRADE-2.8.md b/UPGRADE-2.8.md
index ae8bb7fa4a..67e1c0e66f 100644
--- a/UPGRADE-2.8.md
+++ b/UPGRADE-2.8.md
@@ -505,3 +505,11 @@ Config
    Additionally, if you have implemented cache validation strategies *using* `isFresh()`
    yourself, you should have a look at the new cache validation system based on
    `ResourceChecker`s.
+
+Yaml
+----
+
+ * Deprecated usage of a colon in an unquoted mapping value
+ * Deprecated usage of `@`, `` ` ``, `|`, and `>` at the beginning of an unquoted string
+ * Deprecated non-escaped \ in double-quoted strings when parsing Yaml
+   ("Foo\Var" is not valid whereas "Foo\\Var" is)
diff --git a/UPGRADE-3.0.md b/UPGRADE-3.0.md
index 65386359a5..5b86950fc6 100644
--- a/UPGRADE-3.0.md
+++ b/UPGRADE-3.0.md
@@ -1228,6 +1228,11 @@ UPGRADE FROM 2.x to 3.0
 
 ### Yaml
 
+ * Using a colon in an unquoted mapping value leads to a `ParseException`.
+ * Starting an unquoted string with `@`, `` ` ``, `|`, or `>` leads to a `ParseException`.
+ * Deprecated non-escaped \ in double-quoted strings when parsing Yaml
+   ("Foo\Var" is not valid whereas "Foo\\Var" is)
+
  * The ability to pass file names to `Yaml::parse()` has been removed.
 
    Before:
diff --git a/src/Symfony/Component/Yaml/CHANGELOG.md b/src/Symfony/Component/Yaml/CHANGELOG.md
index a6a8612f37..ccfdb1a792 100644
--- a/src/Symfony/Component/Yaml/CHANGELOG.md
+++ b/src/Symfony/Component/Yaml/CHANGELOG.md
@@ -4,7 +4,8 @@ CHANGELOG
 2.8.0
 -----
 
- * Deprecated usage of @ and \` at the beginning of an unquoted string
+ * Deprecated usage of a colon in an unquoted mapping value
+ * Deprecated usage of @, \`, | and > at the beginning of an unquoted string
  * Deprecated non-escaped \ in double-quoted strings when parsing Yaml
    ("Foo\Var" is not valid whereas "Foo\\Var" is)