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Comparison · Comms
Mailu vs Roundcube
A side-by-side editorial comparison of Mailu and Roundcube — release velocity, themes, recent moves, and the top alternatives to consider.
Mailu vs Roundcube: at a glance
What is Mailu?
A mail server whose entire visible output is patching other people's code.
Mailu is a self-hosted mail suite shipped as a Docker compose stack, and the 2024.06.x branch shown here is its maintenance line. Every release in the window is a single-issue patch — a Roundcube bump, a CVE fix, an autoconfig tweak. The cadence looks high at ten pinned releases in five months, but each carries one change.
What is Roundcube?
After four years, Roundcube 1.7 lands — and the release stream is otherwise all CVEs
Roundcube maintains two lines in lockstep: 1.6 as LTS and 1.7 as stable, with security fixes released to both on the same day. The vulnerability stream is heavy and varied — stored XSS via an unescaped attachment MIME type (CVE-2026-54432), a pre-auth SQL injection in the virtuser_query plugin, CSS injection through SVG animate, SSRF bypasses via local address URLs, an infinite loop in the TNEF decoder. Version 1.7.0, released in May after almost four years of development, is the only feature release in the window.
Mailu vs Roundcube: editorial side-by-side
Mailu
5.0COMMS
A mail server whose entire visible output is patching other people's code.
◆ Current state
Mailu is a self-hosted mail suite shipped as a Docker compose stack, and the 2024.06.x branch shown here is its maintenance line. Every release in the window is a single-issue patch — a Roundcube bump, a CVE fix, an autoconfig tweak. The cadence looks high at ten pinned releases in five months, but each carries one change.
◆ Where it's heading
Most of what Mailu ships is downstream maintenance of its bundled components, Roundcube above all, which drove three of these ten releases. The project's own work here is defensive: escaping user-controlled fields in generated sieve scripts, setting X-Forwarded-By, adapting to Microsoft's new autodiscover. This is a product in steady-state operation, where the release notes track what upstream broke rather than what Mailu decided to build.
◆ Prediction
The next pinned release will most likely be another Roundcube or Alpine bump, since component upgrades triggered half the releases here. These entries say nothing about what is happening on the main branch.
Roundcube
5.0COMMS
After four years, Roundcube 1.7 lands — and the release stream is otherwise all CVEs
◆ Current state
Roundcube maintains two lines in lockstep: 1.6 as LTS and 1.7 as stable, with security fixes released to both on the same day. The vulnerability stream is heavy and varied — stored XSS via an unescaped attachment MIME type (CVE-2026-54432), a pre-auth SQL injection in the virtuser_query plugin, CSS injection through SVG animate, SSRF bypasses via local address URLs, an infinite loop in the TNEF decoder. Version 1.7.0, released in May after almost four years of development, is the only feature release in the window.
◆ Where it's heading
The arc is a long-lived webmail codebase paying down structural risk. 1.7.0's headline changes are defensive rather than user-facing: a mandatory public_html/ entry point so installations aren't exposed by default, improved OAuth2/OIDC support including discovery and logout, removed code bloat and automated code style and quality checks. Everything since has been paired security releases across both lines, several of them reporting classes of bug — sanitizer bypasses, injection through plugin queries — that the 1.7 hardening work is aimed at. Expect the security cadence to stay high while the 1.6 LTS remains supported.
◆ Prediction
Expect continued same-day paired security releases on 1.6 and 1.7, with 1.7.x accruing incremental OIDC and sanitizer hardening before any 1.8 work becomes visible.
Alternatives to Mailu and Roundcube
Other Comms products tracked by Sparkpulse, ranked by recent ship velocity. Each card links to a full editorial trajectory and lets you pivot into a head-to-head comparison with either Mailu or Roundcube.
Chatwoot
Chatwoot added voice, then pointed its AI agent at the tickets it already resolved.
Signal Desktop
Signal's beta train is quietly handing group admins real moderation powers.
Notion
Notion is turning itself into the place other companies' agents come to work.
Slack
Slack's app platform is being rebuilt around agents, with the SDKs clearing old ground behind it.
Bird
Monthly digests showing AI chat latency cut hard, in a feed that repeats itself
See all Mailu alternatives → · See all Roundcube alternatives →
Recent activity from Mailu and Roundcube
Latest ship moves from both products, interleaved chronologically. ⚡ = editorial spark.
- 5d agoMailuAutoconfig fix for modern K-9 Mail
- 7d agoMailuRoundcube 1.6.17 closes two CVEs
- 12d agoMailuSets X-Forwarded-By in response to a GHSA advisory
- 26d agoMailuAdmin UI keeps form values on failed submit
- 26d agoRoundcubeRoundcube LTS patches attachment XSS, SSRF and a TNEF loop
- 26d agoRoundcubeRoundcube 1.7 gets the same attachment XSS and SSRF fixes
- 1mo agoMailuEscapes sieve fields, fixing autoreplies with special characters
- 1mo agoRoundcubeRoundcube LTS fixes a pre-auth SQL injection in virtuser_query
- 1mo agoRoundcubeRoundcube 1.7.1 carries the pre-auth SQL injection fixes
- 2mo agoMailuRoundcube 1.6.16 and carddav 5.1.3 close CVE-2026-49217
- 2mo agoRoundcubeRoundcube Webmail 1.7.0 ⚡
- 4mo agoRoundcubeRoundcube 1.6.15 fixes an SVG animate bypass and search regressions
Frequently asked questions
What is the difference between Mailu and Roundcube?
They serve adjacent needs but don't currently overlap on shipped themes. Mailu and Roundcube are shipping at a similar cadence (velocity 5.0 vs 5.0, both within Sparkpulse's "active" band). See the at-a-glance table above for a side-by-side breakdown of velocity, recent sparks, and editorial themes.
Is Mailu better than Roundcube?
Sparkpulse doesn't pick a winner — we score release velocity, not feature parity. Mailu and Roundcube are shipping at a similar cadence (velocity 5.0 vs 5.0, both within Sparkpulse's "active" band). For your specific use case, the alternatives sections above list other Comms products to evaluate alongside.
What are the best alternatives to Mailu?
Top Mailu alternatives in Comms are ranked by recent ship velocity. Browse the "Mailu alternatives" section above for the current picks, or visit /alternatives/mailu for the full list with editorial commentary on each.
What are the best alternatives to Roundcube?
Top Roundcube alternatives in Comms are ranked by recent ship velocity. Browse the "Roundcube alternatives" section above for the current picks, or visit /alternatives/roundcube for the full list with editorial commentary on each.