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Smush

12known security flaws found in Smush
since September 2017

Safe from 4.3.4

Version 4.3.4 or later fixes all of them. A site on an older version is open to them.

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When they were found.

Major: Reading files, September 2017Advisory: a security flaw, October 2017Advisory: Cross-site scripting, December 2018Advisory: Running code, December 2018Advisory: Cross-site scripting, December 2018Minor: Cross-site scripting, May 2022Minor: Missing checks, June 2024Minor: Reading files, March 2025Advisory: Running code, August 2026Major: Knocking it over, August 2026Advisory: Missing checks, August 202620172019202120232025

DangerousMajorMinorAdvisory

What they could let someone do.

What could happen

  • Reading files

    Someone could read files on the server they should never see, such as the settings file holding the database password, or delete files the site needs.

    How: The software takes a file name from a request and does not check that it stays inside its own folder.

    Read about it here
  • Knocking it over

    Someone could slow the site down or stop it answering, by sending requests that use up all its memory or time.

    How: Certain input makes the software do far more work than it should, so a handful of requests is enough to tie it up.

    Read about it here
  • Cross-site scripting

    Someone could make your pages run their own script in visitors' browsers, to steal logins, show a fake payment form or send people to a scam site.

    How: The software puts text it was sent back onto a page without making it safe first, so a script hidden in a link, form or comment runs as if it were part of your site.

    Read about it here
Every known flaw, newest first (12)
  1. August 2026AdvisoryRunning codeFixed in 4.3.2. Needs a login on the site (Administrator+).
  2. August 2026MajorKnocking it overFixed in 4.3.0. No login needed.
  3. August 2026AdvisoryMissing checksFixed in 4.3.4.
  4. March 2025MinorReading filesFixed in 3.17.1. Needs a login on the site.
  5. June 2024MinorMissing checksFixed in 3.16.5. Needs a login on the site.
  6. May 2022MinorCross-site scriptingFixed in 3.9.9. No login needed.
  7. December 2018AdvisoryCross-site scriptingFixed in 3.0.0.
  8. December 2018AdvisoryRunning codeFixed in 3.0.1.
  9. December 2018AdvisoryCross-site scriptingFixed in 3.0.0.
  10. October 2017AdvisoryA security flawFixed in 2.7.6.
  11. September 2017MajorReading filesFixed in 2.7.6. No login needed.
  12. Date not knownAdvisoryRunning codeFixed in 3.9.9.

From the public lists of known flaws, checked daily. A flaw is listed once it is made public, often after a fix is out.

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