Editing Patch (computing) (section)

== Software update systems ==
[[File:Brave 1.57.62.0 Software Update on macOS 11.7.7.png|thumb|A [[Sparkle (software)|Sparkle]] software update prompt on macOS]]
{{See also|Category:Software update managers|Push technology|Pull technology|Software verification}}
Software update systems allow for updates to be managed by users and software developers. In the [[Petya (malware)|2017 Petya cyberpandemic]], the financial software "MeDoc"'s update system is said to have been compromised to spread [[malware]] via its updates.<ref>{{cite web|last1=Thomson|first1=Iain|title=Virus (cough, cough, Petya) goes postal at FedEx, shares halted|website=[[The Register]]|url=https://www.theregister.co.uk/2017/06/28/fedex_tnt_express_virus_attack/|access-date=29 June 2017|archive-date=1 July 2017|archive-url=https://web.archive.org/web/20170701083047/https://www.theregister.co.uk/2017/06/28/fedex_tnt_express_virus_attack/|url-status=live}}</ref><ref>{{cite web|title=New Petya Distribution Vectors Bubbling to Surface|url=https://threatpost.com/new-petya-distribution-vectors-bubbling-to-surface/126577/|publisher=Threatpost|access-date=29 June 2017|date=28 June 2017|archive-date=28 June 2017|archive-url=https://web.archive.org/web/20170628194924/https://threatpost.com/new-petya-distribution-vectors-bubbling-to-surface/126577/|url-status=live}}</ref> On the Tor Blog, cybersecurity expert Mike Perry states that [[Deterministic compilation|deterministic]], distributed builds are likely the only way to defend against malware that attacks the software development and [[software build|build]] processes to infect millions of machines in a single, officially signed, instantaneous update.<ref>{{cite web|title=Deterministic Builds Part One: Cyberwar and Global Compromise {{!}} The Tor Blog|url=https://blog.torproject.org/blog/deterministic-builds-part-one-cyberwar-and-global-compromise|website=blog.torproject.org|access-date=11 July 2017|language=en|archive-date=23 June 2017|archive-url=https://web.archive.org/web/20170623204246/https://blog.torproject.org/blog/deterministic-builds-part-one-cyberwar-and-global-compromise|url-status=live}}</ref> Update managers also allow for security updates to be applied quickly and widely. Update managers of [[Linux]] such as [[Synaptic (software)|Synaptic]] allow users to update all software installed on their machine.  Applications like Synaptic use cryptographic checksums to verify source/local files before they are applied to ensure fidelity against malware.<ref>{{cite book|last1=Proffitt|first1=Brian|title=Introducing Ubuntu: Desktop Linux|date=2008|publisher=Cengage Learning|isbn=978-1598637656|url=https://books.google.com/books?id=Fe8LAAAAQBAJ&pg=PA141|access-date=11 July 2017|language=en}}</ref><ref>{{cite book|last1=Magazines|first1=S. P. H.|title=HWM|date=2007|publisher=SPH Magazines|url=https://books.google.com/books?id=G-sDAAAAMBAJ&pg=PT96|access-date=11 July 2017|language=en}}</ref>