Recommend against SHA-1 and MD5 for security

* doc/lispref/text.texi (Checksum/Hash):
* src/fns.c (Fmd5, Fsecure_hash):
* lisp/subr.el (sha1): Doc fix to recommend against SHA-1 and MD5 for
security-related applications, since they are not collision
resistant.  (Bug#37420)

1 files changed, 6 insertions, 6 deletions

diff --git a/doc/lispref/text.texi b/doc/lispref/text.texi
index 7ce54f59c69..955ad6130ca 100644
--- a/doc/lispref/text.texi
+++ b/doc/lispref/text.texi
@@ -4710,12 +4710,12 @@ that you have an unaltered copy of that data.
 SHA-1, SHA-2, SHA-224, SHA-256, SHA-384 and SHA-512.  MD5 is the
 oldest of these algorithms, and is commonly used in @dfn{message
 digests} to check the integrity of messages transmitted over a
-network.  MD5 is not collision resistant (i.e., it is possible to
-deliberately design different pieces of data which have the same MD5
-hash), so you should not used it for anything security-related.  A
-similar theoretical weakness also exists in SHA-1.  Therefore, for
-security-related applications you should use the other hash types,
-such as SHA-2.
+network.  MD5 and SHA-1 are not collision resistant (i.e., it is
+possible to deliberately design different pieces of data which have
+the same MD5 or SHA-1 hash), so you should not use them for anything
+security-related.  For security-related applications you should use
+the other hash types, such as SHA-2 (e.g. @code{sha256} or
+@code{sha512}).
 
 @defun secure-hash-algorithms
 This function returns a list of symbols representing algorithms that