<oembed><type>rich</type><version>1.0</version><author_name>npub1cmt6gqyfw3sdngkq0wadtpe3kmgyyeld6ad0g2h5tar3kpzcrmpqddwkls</author_name><author_url>https://nostr.ae/npub1cmt6gqyfw3sdngkq0wadtpe3kmgyyeld6ad0g2h5tar3kpzcrmpqddwkls</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2017-02-24&#xA;📝 Original message:On Fri, 2017-02-24 at 00:57 +0100, Aymeric Vitte via bitcoin-dev wrote:&#xA;&gt; &#xA;&gt; I have not worked on this since some time, so that&#39;s just thoughts,&#xA;&gt; but maybe it can render things much more difficult&#xA;&gt; than       computing two files until the same hash is found&#xA;&gt; &#xA;&#xA;You basically rely on the idea that specific collisions are more&#xA;difficult to find. This trick or similar tricks will not help. (And&#xA;actually, the more files you add to the hash, the more freedom you give&#xA;the attacker.)&#xA;&#xA;Even if certain collisions are more difficult to find today (which is&#xA;certainly true), the general rule is that someone will prove you wrong&#xA;in a year.&#xA;&#xA;Even if ignore security entirely, switching to new hash function is&#xA;much simpler trying to fix the usage of a broken hash function.&#xA;&#xA;Relying on SHA1 is hopeless. We have to get rid of it.&#xA;&#xA;Best,&#xA;Tim</html></oembed>