CKEditor 4 End of Life: 2026 Guide, Risks & Options
TL;DR
CKEditor 4 reached its official end of life on June 30, 2023, after an 11-year run. The last free open-source version (4.22.1) contains known security vulnerabilities and should no longer be used in production. Your options now are migrating to CKEditor 5, purchasing CKEditor 4 LTS (extended support until December 2028), switching to an alternative editor like TinyMCE or Froala, or accepting the security risks of doing nothing.
What Is CKEditor 4 End of Life?
End of life (EOL) is the point where a software product’s creator stops maintaining it. No more updates, no security patches, no bug fixes, no new features. The product still functions, but it’s frozen in place while the threat landscape keeps moving.
For CKEditor 4 specifically, EOL became effective on June 30, 2023. The editor launched in November 2012 and served millions of users across content management systems, web applications, and enterprise platforms for over a decade. CKSource, the company behind CKEditor, retired version 4 to focus resources on CKEditor 5, which had reached its first stable release back in 2018.
The critical fact that many teams overlook: the last free open-source version of CKEditor 4 (4.22.1) contains known security issues and should no longer be used. If you’re running that version or anything older, your application has documented vulnerabilities that will never be patched in the free edition.
Why Did CKEditor 4 Reach End of Life?
CKEditor 5 wasn’t an incremental upgrade. It was a ground-up rewrite. CKSource redesigned every aspect of the editor, from its data model and API to its installation process and plugin architecture. Maintaining two fundamentally different products indefinitely wasn’t sustainable.
Eleven years of active support is a long run for any software product. CKSource first announced CKEditor 4’s EOL timeline in 2018, giving teams five years of notice before the cutoff. That’s more lead time than most vendors provide.
The reasoning was straightforward: CKEditor 4 relied heavily on the browser for low-level operations, meaning every tiny difference in behavior across browsers had a huge negative impact. CKEditor 5 re-implemented many of those operations to guarantee consistency. The architectural gap between the two versions made it impractical to keep both alive.
Security Risks of Running EOL CKEditor 4
The security risk isn’t hypothetical. Within months of CKEditor 4 reaching end of life, real vulnerabilities started surfacing with no free patches available.
In January 2024, a significant security issue was identified in CKEditor 4. Specifically:
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CVE-2024-24816: A cross-site scripting (XSS) vulnerability in CKEditor 4 sample files allowed attackers to execute untrusted JavaScript in the context of the currently logged-in user. This was fixed in version 4.24.0-lts, but only for paying LTS customers.
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CVE-2024-37888: A separate XSS vulnerability in the Open Link plugin discovered by NetSPI, again affecting CKEditor 4 installations.
XSS vulnerabilities aren’t minor annoyances. They can lead to session hijacking, data theft, and account takeover. According to CKEditor’s own release notes, all editor versions below 4.25.0-lts can no longer be considered secure.
Doing nothing is itself a decision, and it’s the riskiest one available.
Your Options After CKEditor 4 End of Life
Option 1: Migrate to CKEditor 5
This is the path CKSource recommends, but it comes with significant caveats.
CKEditor 5 should be treated as a totally new editor. There is no automatic migration tool. The data model is different, the API is different, and the plugin system is completely rebuilt. A developer who blogged about their experience wrote that migrating from CKEditor 4 to CKEditor 5 was no easy feat, citing issues with image uploads, form widgets, and inline styles.
There’s also a licensing change. CKEditor 5 is available only under a GPL 2+ copyleft open-source license. Commercial projects that previously used CKEditor 4 for free under its more permissive open-source license will need to purchase a commercial license for CKEditor 5. Pricing starts at $144 per month for the Essential plan.
Perhaps the biggest pain point: content not compatible with enabled features in CKEditor 5 may be lost during migration. CKEditor 5 adapts and transforms data to align with its supported features, so existing HTML content may change in unexpected ways.
The Drupal community felt this acutely. Approximately 450,000 Drupal 8 and 9 sites needed to migrate from CKEditor 4 to 5, and the project’s documentation acknowledged that “virtually every detail is different.”
Option 2: Purchase CKEditor 4 LTS
CKSource offers CKEditor 4 LTS as a commercial extended support package that guarantees security updates and critical bug fixes until December 2028. This buys time without requiring an immediate migration.
The catch: pricing is not publicly listed and depends on multiple factors. There’s no self-service purchase system. You’ll need to contact CKSource directly to negotiate terms.
For teams that rely on track changes or inline comments in their CKEditor 4 setup, the LTS path preserves those workflows while keeping the editor secure through 2028.
Option 3: Switch to a Different Editor
TinyMCE, Froala, Tiptap, and Quill are the main alternatives that surface in community discussions. As practitioners on the ProcessWire forums noted, if you’re forced to stop using CKEditor 4 due to EOL, what you really need is a drop-in replacement, not a complete rewrite of your editing infrastructure.
Switching editors takes roughly the same effort as migrating to CKEditor 5, since neither path is a simple upgrade. The advantage of switching is that you get to evaluate the full market and pick the editor that best fits your current needs rather than being locked into CKSource’s ecosystem.
If you’re considering TinyMCE, collaboration features like track changes for TinyMCE and inline comments for TinyMCE are available through third-party plugins. The same applies to Froala, with track changes for Froala and inline comments for Froala covering that editor’s ecosystem.
Option 4: Keep Running CKEditor 4 (Not Recommended)
Your CKEditor 4 installation will continue to work. The editor doesn’t stop functioning because of an EOL date. But the lack of patches, releases, and support may leave you vulnerable to security threats.
This option is only defensible for internal tools with no exposure to untrusted input, and even then, it accumulates risk over time. For anything public-facing or handling sensitive data, this is a non-starter.
What Happens to CKEditor 4 Plugins and Integrations?
This is where the CKEditor 4 end of life creates the most frustration for development teams.
CKEditor 5’s plugin architecture is completely different from CKEditor 4’s. Your existing CKEditor 4 plugins will not work in CKEditor 5. As the CKEditor documentation states, custom plugins developed for CKEditor 4 must be rewritten from scratch for CKEditor 5. The concept may stay the same, but the implementation will be entirely new.
Practitioners on the vBulletin forums echoed this concern, noting that upgrading to CKEditor 5 is a major upgrade that would likely require a full version bump of their platform. One community member added that while CKEditor 4 may be “old school,” its replacement introduces its own challenges around responsive layouts and load times.
Third-party plugins built for CKEditor 4 (like track changes and inline comments) continue to work with CKEditor 4 itself, including the LTS version. The question is what happens when you eventually move away from CKEditor 4 entirely.
Teams evaluating their options should check whether the plugins they depend on are available for their target editor. Collaboration features like track changes and inline comments are available across multiple editors, so switching from CKEditor 4 to TinyMCE or Froala doesn’t have to mean losing those workflows. See pricing for track changes and inline comments plugins to compare costs across supported editors.
Key Dates and Timeline
| Date | Event |
|---|---|
| November 2012 | CKEditor 4 launched |
| 2018 | CKEditor 5 first stable release; CKEditor 4 EOL first announced |
| June 30, 2023 | CKEditor 4 end of life effective |
| January 2024 | First significant post-EOL security issue discovered (CVE-2024-24816) |
| 2024 | CVE-2024-37888 (XSS in Open Link plugin) disclosed |
| December 2028 | CKEditor 4 LTS extended support end date |
Frequently Asked Questions
Does CKEditor 4 still work after end of life?
Yes. The editor continues to function normally. EOL means no new updates, security patches, or official support, not that the software stops running. However, every day you run it without patches increases your exposure to known vulnerabilities.
Is CKEditor 4 LTS free?
No. The LTS extended support package is a commercial product with flexible pricing. CKSource doesn’t publish prices publicly, so you’ll need to contact them directly for a quote.
Can I migrate CKEditor 4 plugins to CKEditor 5?
Not directly. CKEditor 5 has a completely different plugin architecture. Custom plugins must be rewritten from scratch. Even the way content is processed and represented in HTML differs between the two versions.
What about Drupal sites still using CKEditor 4?
As of January 1, 2024, the open-source edition of CKEditor 4 ceased to receive security updates in the Drupal ecosystem. Drupal 10 and later ship with CKEditor 5 as the default, but sites on Drupal 8 or 9 may still be running CKEditor 4. The XWiki project, for example, discovered in March 2025 that all their current releases still used CKEditor 4.x, years after EOL.
What editors support track changes and inline comments like CKEditor 4?
Track changes and inline comments are available as third-party plugins for TinyMCE, Froala, and CKEditor 4. This means teams switching editors can preserve their collaboration workflows. Check who uses track changes plugins to see if your use case is covered.
How long do I have before I absolutely must migrate?
If you’re on the CKEditor 4 LTS plan, you have until December 2028. If you’re on the free open-source version, you’re already running software with known, unpatched security vulnerabilities. The urgency depends on your threat model, but for public-facing applications, the answer is “now.”
What’s the biggest hidden cost of migration?
Custom plugin rewrites. Teams that built bespoke CKEditor 4 plugins often underestimate the effort required to recreate them for CKEditor 5 or a different editor. Budget for this work early. If your team needs guidance on maintaining collaboration features during a migration, contact the Loop Index team for help evaluating plugin compatibility across editors.