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Regular Expression · passage 1 of 3

Regular Expression

Text · Regular Expression/README.md

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> Regular Expression Denial of Service (ReDoS) is a type of attack that exploits the fact that certain regular expressions can take an extremely long time to process, causing applications or services to become unresponsive or crash.

Source: Regular Expression/README.md in PayloadsAllTheThings. From PayloadsAllTheThings by Swissky and contributors. MIT License, Copyright (c) 2019 Swissky.

Every one of the 3 is a mark on the map. Named now: 1 to 3, reading order first.

  1. Regular Expression§ 1text · README.md
  2. Evil Regex§ 21 code block · README.md
  3. Backtrack Limit§ 33 code blocks · README.md

Zoom in on the map and the dots under the middle of it are named where they are.

Data as of 2026-11-15. CVE List through 2026-11-15 · EPSS of 2026-11-14 · CISA KEV checked 2026-11-15. Source: PayloadsAllTheThings by Swissky and contributors, MIT License. For authorised testing only.