{"slug": "when-su-replaced-login-for-becoming-another-unix-login", "title": "When su replaced login for becoming another Unix login", "summary": "A blog owner blocked access to their site for users of outdated browsers, particularly old Chrome versions, due to a surge of high-volume crawlers suspected of gathering data for LLM training in early 2025. The block also affects users of feed readers like Inoreader and Feedly, which fetch feeds with old browser user agents, and Vivaldi users with brand masking enabled. The owner advises affected legitimate users to contact them with their browser details or switch to archive.org for archival access.", "body_md": "You're probably reading this page because you've attempted to access\nsome part of [my blog (Wandering Thoughts)](../space/blog/) or\n[CSpace](../space/), the wiki thing it's part of. Unfortunately\nyou're using a browser version that my anti-crawler precautions consider\nsuspicious, most often because it's too old (most often this applies to\nversions of Chrome). Unfortunately, as of early 2025 there's a plague\nof high volume crawlers (apparently in part to gather data for LLM\ntraining) that use a variety of old browser user agents, especially\nChrome user agents. To reduce the load on\n[Wandering Thoughts](../space/blog/) I'm experimenting with\n(attempting to) block all of them, and you've run into this.\n\nIf this is in error and you're using a current version of your\nbrowser of choice, you can contact me at [my current place at the\nuniversity](https://www.cs.toronto.edu/~cks/) (you should be able to work out the email address\nfrom that). If possible, please let me know what browser you're\nusing and so on, ideally with its exact User-Agent string.\n\nI am not blocking Inoreader's feed fetcher or considering it to be\ntoo old, and it routinely fetches feeds from me. I don't know why\nInoreader is showing you this page. It is possible that they're\nperiodically trying to fetch feeds or pages with an old browser\nHTTP User-Agent (or an actual old browser) and taking the results\nof that fetch (this page) as what they should show people instead\nof the results of their syndication feed fetcher agents. This is a\nbad mistake today; [the results\nof modern HTTP fetches depend partly on the HTTP User-Agent used](/~cks/space/blog/web/HTTPResultsAndUserAgents).\n\nMuch like Inoreader, Feedly is periodically fetching my syndication\nfeeds with a fake, old browser HTTP User-Agent header, which fails,\nand is then grimly latching on to the results for their actual feed\nfetching with their regular Feedly HTTP User-Agent. There is nothing\nI can do about this; you should contact Feedly support, if you can\nfind them. See [this\ncomment of mine in Wandering Thoughts](https://utcc.utoronto.ca/~cks/space/blog/web/FeedReaderErrorsProblem?showcomments#cks-20260215115901) for more details.\n\nDue to an ongoing attack, you may need to change\n[the\n\"User Agent Brand Masking\" setting](https://help.vivaldi.com/desktop/miscellaneous/user-agent-brand-masking/) so that your Vivaldi identifies\nitself as Vivaldi, instead of Google Chrome. This applies to even\nthe current version of Vivaldi.\n\nYou may be seeing this through archive.today, archive.ph, archive.is,\nand so on. Unfortunately, archive.* crawls pages to archive in a way that\nis impossible to distinguish from malicious actors. They use old Chrome\nUser-Agent values, crawl from IP address blocks that are widely distributed\nand not clearly identified as theirs, and some of their IP addresses have\nfalsified reverse DNS entries that claim they are googlebot IP addresses\n(which is something that is normally done only by quite bad actors). I\nsuggest that you use archive.org, which is a better behaved archival\ncrawler and can crawl [my blog (Wandering Thoughts)](../space/blog/).", "url": "https://wpnews.pro/news/when-su-replaced-login-for-becoming-another-unix-login", "canonical_source": "https://utcc.utoronto.ca/~cks/space/blog/unix/SuAsLoginReplacement", "published_at": "2026-06-04 11:36:00+00:00", "updated_at": "2026-06-04 11:48:43.209747+00:00", "lang": "en", "topics": ["artificial-intelligence", "large-language-models", "ai-ethics", "ai-research", "ai-policy"], "entities": ["Wandering Thoughts", "CSpace", "Chrome", "Inoreader", "University of Toronto"], "alternates": {"html": "https://wpnews.pro/news/when-su-replaced-login-for-becoming-another-unix-login", "markdown": "https://wpnews.pro/news/when-su-replaced-login-for-becoming-another-unix-login.md", "text": "https://wpnews.pro/news/when-su-replaced-login-for-becoming-another-unix-login.txt", "jsonld": "https://wpnews.pro/news/when-su-replaced-login-for-becoming-another-unix-login.jsonld"}}