# CVE-2026-7635: Deserialization in coreActivity: Activity Logging for WordPress

> Unauthenticated attackers can cause persistent denial of service by injecting serialized payloads via User-Agent headers, blocking admin access to logs.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 13 May 2026
- **Updated:** 13 May 2026

## What is CVE-2026-7635?

CVE-2026-7635 is a high-severity unsafe deserialization vulnerability in gdragon coreActivity: Activity Logging for WordPress, published on 13 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The coreActivity: Activity Logging for WordPress plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 3.0. This is due to the plugin failing to validate or strip PHP serialization syntax from the User-Agent HTTP header before storing it in the logmeta table, and subsequently calling `maybe_unserialize()` on every retrieved `meta_value` in `query_metas()` without verifying the data was originally serialized by the application. This makes it possible for unauthenticated attackers to inject a crafted PHP serialized payload via the User-Agent header during any logged event (such as a failed login attempt), which, when an administrator views the Logs page, is deserialized and passed to `DeviceDetector::setUserAgent()`, triggering a Fatal TypeError that creates a persistent Denial of Service condition blocking administrator access to the Logs page entirely.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2026-7635?


## How do I fix CVE-2026-7635?

No fix has been published for CVE-2026-7635 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-7635 being exploited?

There is no known exploitation of CVE-2026-7635 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-7635 and fix it if it is affected.

What it is: CVE-2026-7635 is a high-severity unsafe deserialization vulnerability in gdragon coreActivity: Activity Logging for WordPress, published on 13 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-7635 in the wild and no public exploit code.

Affected product: gdragon coreActivity: Activity Logging for WordPress. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-7635/ (Markdown: https://insights.sbomify.com/CVE-2026-7635/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-7635
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-7635
- OSV: https://osv.dev/vulnerability/CVE-2026-7635

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-7635/
Summaries are generated and may contain mistakes; the official description above is the record.