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Yoast SEO

34known security flaws found in Yoast SEO
since October 2012

Safe from 28.1

Version 28.1 or later fixes all of them. A site on an older version is open to them.

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When they were found.

Advisory: Cross-site scripting, October 2012Advisory: Missing checks, August 2014Advisory: Forged requests, March 2015Advisory: Database injection, March 2015Advisory: Cross-site scripting, April 2015Advisory: Cross-site scripting, April 2015Advisory: Information leak, May 2016Advisory: Information leak, May 2016Advisory: Cross-site scripting, June 2016Advisory: Cross-site scripting, June 2016Advisory: a security flaw, July 2016Advisory: a security flaw, July 2016Minor: Cross-site scripting, August 2016Advisory: Cross-site scripting, August 2016Advisory: Forged requests, May 2017Minor: Cross-site scripting, November 2017Advisory: Cross-site scripting, November 2017Minor: a security flaw, November 2018Advisory: a security flaw, November 2018Dangerous: Cross-site scripting, July 2019Minor: Information leak, October 2021Advisory: Cross-site scripting, March 2023Advisory: Cross-site scripting, March 2023Minor: Cross-site scripting, November 2023Minor: Cross-site scripting, May 2024Minor: Cross-site scripting, May 2024Advisory: Cross-site scripting, February 2026Advisory: Cross-site scripting, March 2026Minor: Missing checks, May 2026Advisory: Cross-site scripting, July 202620122014201620182020202220242026

DangerousMajorMinorAdvisory

What they could let someone do.

What could happen

  • 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
  • Information leak

    It could give away information that should stay private, such as user details, file locations or settings, which makes other attacks easier.

    How: The software shows, sends or logs more than it should.

  • Missing checks

    Someone could do things only an administrator should: change settings, see private data, or give themselves more rights.

    How: Part of the software forgets to check who is asking before it does what was asked.

    Read about it here
Every known flaw, newest first (34)
  1. July 2026AdvisoryCross-site scriptingFixed in 28.1. Needs a login on the site (Author+).
  2. May 2026MinorMissing checksFixed in 26.6. Needs a login on the site (Contributor+).
  3. March 2026AdvisoryCross-site scriptingFixed in 27.2. Needs a login on the site (Contributor+).
  4. February 2026AdvisoryCross-site scriptingFixed in 26.9. Needs a login on the site (Contributor+).
  5. May 2024MinorCross-site scriptingFixed in 22.7. Needs a login on the site (Contributor+).
  6. May 2024MinorCross-site scriptingFixed in 22.6. No login needed.
  7. November 2023MinorCross-site scriptingFixed in 21.1. Needs a login on the site.
  8. March 2023AdvisoryCross-site scriptingFixed in 20.2.1.
  9. March 2023AdvisoryCross-site scriptingFixed in 20.2.1. Needs a login on the site (Contributor+).
  10. October 2021MinorInformation leakFixed in 17.3. No login needed.
  11. July 2019DangerousCross-site scriptingFixed in 11.6. No login needed.
  12. November 2018AdvisoryA security flawFixed in 9.2.0.
  13. November 2018MinorA security flawFixed in 9.2.0. Needs a login on the site.
  14. November 2017AdvisoryCross-site scriptingFixed in 5.8.0. No login needed.
  15. November 2017MinorCross-site scriptingFixed in 5.8.0. Needs a login on the site.
  16. May 2017AdvisoryForged requestsFixed in 3.3.2.
  17. August 2016AdvisoryCross-site scriptingFixed in 3.4.1.
  18. August 2016MinorCross-site scriptingFixed in 3.4.1. Needs a login on the site.
  19. July 2016AdvisoryA security flawFixed in 1.4.5.
  20. July 2016AdvisoryA security flawFixed in 1.4.7.
  21. June 2016AdvisoryCross-site scriptingFixed in 3.3.0.
  22. June 2016AdvisoryCross-site scriptingFixed in 3.3.0.
  23. May 2016AdvisoryInformation leakFixed in 3.2.5.
  24. May 2016AdvisoryInformation leakFixed in 3.2.5.
  25. April 2015AdvisoryCross-site scriptingFixed in 2.1.
  26. April 2015AdvisoryCross-site scriptingFixed in 2.1.
  27. March 2015AdvisoryDatabase injectionFixed in 1.7.4.
  28. March 2015AdvisoryForged requestsFixed in 1.7.4.
  29. August 2014AdvisoryMissing checksFixed in 1.4.7.
  30. October 2012AdvisoryCross-site scriptingFixed in 2.2.
  31. Date not knownAdvisoryCross-site scriptingFixed in 3.3.0.
  32. Date not knownAdvisoryInformation leakFixed in 3.2.5.
  33. Date not knownAdvisoryA security flawFixed in 1.4.7.
  34. Date not knownAdvisoryA security flawFixed in 1.4.5.

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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