XKCD | Website 2026-10-21

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Other numbers are largely unaffected, but anyone using ‘4’ for their certificate key is urged to upgrade to 5.

Transcript

1 Panel Comic

Cueball sits at a desk with his hands folded to report on an unfolding story.

Cueball: Breaking: Mathematicians have announced a critical vulnerability in the number line affecting the integer between 2 and 4. Until the patch is applied, if you must count small numbers of objects, please use the alternatives “half six” or “baker’s two.”