From: Stefan Kangas <stefan@marxist.se>
To: 37420@debbugs.gnu.org
Subject: bug#37420: [PATCH] Recommend against SHA-1 for security-related applications
Date: Mon, 16 Sep 2019 10:53:27 +0200 [thread overview]
Message-ID: <CADwFkmmdMPd_yVSxfGWU0X19F_kEQvcscZ6YLRs66AVyiXhV9g@mail.gmail.com> (raw)
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SHA-1 has now seen collision attacks:
https://www.zdnet.com/article/sha-1-collision-attacks-are-now-actually-practical-and-a-looming-danger/
We should clarify that these attacks are not only theoretical, and
actively discourage using it in security-related applications in the
Elisp Manual. The attached patch is an attempt at doing that.
Any comments?
Best regards,
Stefan Kangas
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From 53a42470604e3db6e2f0552eb3481fa64a853458 Mon Sep 17 00:00:00 2001
From: Stefan Kangas <stefankangas@gmail.com>
Date: Mon, 16 Sep 2019 10:45:14 +0200
Subject: [PATCH] Recommend against SHA-1 for security-related applications
* doc/lispref/text.texi (Checksum/Hash): Clarify that SHA-1 is not
collision resistant.
---
doc/lispref/text.texi | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/doc/lispref/text.texi b/doc/lispref/text.texi
index 7ce54f59c6..949797c3ef 100644
--- a/doc/lispref/text.texi
+++ b/doc/lispref/text.texi
@@ -4710,12 +4710,12 @@ Checksum/Hash
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 (@code{sha224}, @code{sha256},
+@code{sha384} or @code{sha512}).
@defun secure-hash-algorithms
This function returns a list of symbols representing algorithms that
--
2.20.1
next reply other threads:[~2019-09-16 8:53 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-16 8:53 Stefan Kangas [this message]
2019-09-16 11:21 ` bug#37420: [PATCH] Recommend against SHA-1 for security-related applications Lars Ingebrigtsen
2019-09-16 20:29 ` Stefan Kangas
2019-09-16 20:34 ` Lars Ingebrigtsen
2019-09-16 21:50 ` Stefan Kangas
2019-09-16 22:25 ` Lars Ingebrigtsen
2019-09-17 9:17 ` Stefan Kangas
2019-09-17 6:05 ` Eli Zaretskii
2019-09-17 13:37 ` Robert Pluim
2019-09-28 10:19 ` Stefan Kangas
2019-09-28 19:55 ` Lars Ingebrigtsen
2019-10-04 15:33 ` Stefan Kangas
2019-09-17 5:50 ` Eli Zaretskii
2019-09-17 9:09 ` Stefan Kangas
2019-09-17 11:53 ` Eli Zaretskii
2019-09-17 12:08 ` Stefan Kangas
2019-09-17 12:14 ` Stefan Kangas
2019-09-20 18:50 ` Stefan Kangas
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