Host Header Injection Fix
by Jeff Starr · Email & Marketing
Also makes 30 other plugins · 1.1M+ installs across the portfolio →
Sets custom headers for WP notification emails. Also fixes a security issue with WP versions < 5.5.
Try it live opens a temporary test site in your browser, which can take about 20 seconds to load. Plugins that rely on outside services or a full server may not work completely there.
Health
A 85/100
Few reviews
Active installs
400+
≈480 estimated
Momentum
+15%
downloads vs prior 30d
Biggest opportunity: Swap “email” and “headers” for “fix” and “host”. “email” isn't earning its slot: you're not in the first 24 results for its own search. “fix” sits at #6 untagged, close enough for a declared tag to move it up. “headers” isn't earning its slot: you're not in the first 24 results for its own search. “host” sits at #7 untagged, close enough for a declared tag to move it up. All five slots are taken, so one has to go.
85 health vs 66 average across 2,120 Email & Marketing plugins
Install conversion
How it's measured →1.4%
of downloads still active
At least 400 of 27.7K lifetime downloads are still running, above its category: the median Email & Marketing plugin keeps 0.9%, across 1,294 plugins.
Downloads count every update, not just first installs, so older and more frequently released plugins read lower. Compare against other Email & Marketing plugins, not across the directory. wp.org reports active installs as the bottom of a band, so the real rate is this or higher.
This plugin shipped 4 releases in the last 12 months, and every existing install that updated counted as another download. wp.org publishes no split between first installs and updates, so we show the raw rate rather than guess at one.
Details
Directory ranking optimization
How it's scored →How well this listing is tuned to rank in WordPress.org search, on the factors an owner controls. Not popularity, optimization.
Excellent listing optimization
Most to gain: Rating quality
Updated 105 days ago
Tested up to WordPress 7.1.4, the current branch or newer
5.0★ over 6 reviews, smoothed to 4.20★ and held back under 25 reviews
5 of 5 tags set · short description in place
To rank higher: Too few reviews to rank on quality — nudge happy users to leave one.
Get the full rank-higher report →Search visibility
How it's tracked →Directory searches this plugin turns up in, and which way each one is moving. WordPress.org publishes no history of search positions, so this starts the day we first tracked a keyword and never backfills.
41
Momentum
Mixed: one swing, the rest drifting
+0.3
Velocity
places per keyword, 28d
22%
Breadth
of keywords climbing, 28d
+0.2
Acceleration
recent half vs earlier
wp.org is where the directory puts the plugin for that search. On merit is where it would sit if results were ranked on rating, support and updates, without the install boost. The last column is how far the wp.org position moved, from our first reading in the last 90 days to the latest.
| Keyword | wp.org | On merit | wp.org move, 90 days |
|---|---|---|---|
| injection your tag | #4 | #14 | 0 |
| fix | #6 | #18 | up 3 |
| host | #7 | #18 | down 1 |
| header notification | #12 | #21 | — |
| email your tag | Not in the top 24 | ||
| headers your tag | Not in the top 24 | ||
| notification your tag | Not in the top 24 | ||
| security your tag | Not in the top 24 | ||
24 searches this plugin appeared in over the last 90 days, 4 listed. 20 left out as unrelated or noise (years, numbers, stray words). 4 of its tags aren't in the top 24 for their own search.
What to do about it
- Swap “email” and “headers” for “fix” and “host”. “email” isn't earning its slot: you're not in the first 24 results for its own search. “fix” sits at #6 untagged, close enough for a declared tag to move it up. “headers” isn't earning its slot: you're not in the first 24 results for its own search. “host” sits at #7 untagged, close enough for a declared tag to move it up. All five slots are taken, so one has to go.
Daily downloads
Since 5 Oct 2022 · 1,488 days · wp.org + Plugin Pulse archive
30-day downloads
Rolling 30-day volume · peak 746 · peaks are release surges
Directory rank vs rivals
wp.org popularity rank over time · higher is better · when a rival's line climbs above yours, they've overtaken you
Health trend
Composite health score, snapshotted daily
Update activity
How busy the existing users are, measured as downloads in the last 30 days for every 1,000 active sites. A spike means a new release everyone's pulling; a long, slow decline means an aging user base that updates less.
Release cadence
Actively maintainedHow often this plugin actually ships. A steady rhythm is the maintenance signal a single "last updated" date can't show.
4
releases in the last 12 months
4mo ago
latest release · v3.7 · 18 Jul 2026
29
tagged releases on record
Recent releases
What its installed base runs
via wordpress.orgShare of active installs on each version of this plugin. Green is the current release; a big slice on older versions is a user base that has stopped updating.
Estimated active installs
The public count shows “400+”. Our estimate pins where the real number sits.
Crossed into this band 2 months ago and a band this size takes about a year or more to cross, so the real count is still just under 500.
Install history since 25 Oct 2020
Behavioral tests
via WP HiveAutomated install-time checks, tested on PHP 8.1.12 · WP 7.0.1
Languages
via translate.wordpress.orgTranslated into 2 languages, 1 at 90% or more
AI assistants
How it's measured →Whether ChatGPT and Claude name this plugin when asked the category question, and whether the readme gives them something to quote.
Not measured yet for this plugin’s topics. Its tracked searches are not among the measured topics. See the topics measured so far.
Readme readiness
5 of 8 pass · checked 28 Oct 2026Can an assistant quote this readme? Eight deterministic checks over the wp.org listing, no model involved.
- ! Says what it does Short description names no action; say what the plugin does for the site.
- ✓ Has a FAQ 8 questions in the FAQ.
- ✓ FAQ asks real questions 8 of 8 read like questions a user would type.
- ! Names who it is for Never says who the plugin is for or what they use it for.
- ✓ Names what it works with Mentions Google Analytics, REST API.
- ! Headings and lists 0 headings and 7 lists; assistants quote headed sections and bullet lists, not paragraphs.
- ✓ Enough to quote 3,912 characters of description.
- ✓ Tags match the text All 5 tags appear in the text.
Growth timeline
Install-tier crossings we have observed, and how long each tier took to outgrow
- 2026-08-18 500+ → 400+ down after 19 days in tier
- 2026-07-30 400+ → 500+ up after 2 days in tier
- 2026-07-28 500+ → 400+ down after 5 days in tier
- 2026-07-23 400+ → 500+ up after 1 days in tier
- 2026-07-22 500+ → 400+ down after 2 days in tier
- 2026-07-20 400+ → 500+ up after 86 days in tier
- 2026-04-25 500+ → 400+ down after 171 days in tier
- 2025-11-05 600+ → 500+ down after 155 days in tier
Competes with
The plugins that solve the same job, ranked by shared tags then reach, closest match first. The letter on the right is each plugin's health grade (A best, F worst).
-
Manage Notification E-mails 100K+ installs · 4.6★ · 2 shared tags A -
WP Hide & Security Enhancer 50K+ installs · 4.3★ · 2 shared tags A -
Disable auto-update Email Notifications 30K+ installs · 4.2★ · 2 shared tags C -
Customize WordPress Emails and Alerts – Better Notifications for WP 30K+ installs · 4.7★ · 2 shared tags A -
Notification – Custom Notifications and Alerts for WordPress 10K+ installs · 4.5★ · 2 shared tags B -
Comment Reply Email Notification 3K+ installs · 4.5★ · 2 shared tags A
Embed this report card
Drop a live Pulse card for Host Header Injection Fix into a readme, a review or a deck. It updates itself.
<iframe src="https://plugins.wpmayor.com/embed/host-header-injection-fix" width="480" height="300" style="border:0" loading="lazy" title="Host Header Injection Fix — Plugin Pulse"></iframe> Host Header Injection Fix: 400+ active installs, 5.0★ (6 reviews). Plugin Pulse (WP Mayor), as of 2026-10-31. https://plugins.wpmayor.com/plugin/host-header-injection-fix
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