---
id: "CVE-2026-116821"
kind: "vulnerability"
aliases: ["CVE-2026-116821"]
title: "YesWiki: wildcard usernames let self-registered users read restricted pages"
severity: "high"
cvss: 7.1
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["php", "runtime", "self-hosted", "yeswiki"]
not_affected_if: ["auth-required", "default-config"]
published_at: "2026-10-27T00:17:16+00:00"
first_seen_at: "2026-10-27T00:25:56+00:00"
updated_at: "2026-10-27T00:26:19+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-116821", "first_seen_at": "2026-10-27T00:25:56+00:00"}]
---

# YesWiki: wildcard usernames let self-registered users read restricted pages

YesWiki before 4.7.0 builds SQL LIKE patterns from usernames without escaping the _ and % wildcards. A self-registered user can pick a name like ___ or %%% to match access tokens meant for others and read pages and Bazar entries restricted to other users or groups through the public Bazar listing API.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed YesWiki version in the wiki's package or version file; `unknown` if the sources do not give the exact location.
- Check whether open self-registration is enabled on the wiki.

## Fix

- Upgrade YesWiki to `4.7.0` or later.
- Until upgraded, disable open self-registration if it is not needed.

## Timeline

- 2026-10-27T00:25:56+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-116821

## From the sources

YesWiki before 4.7.0 contains a read-ACL bypass in AclService::updateRequestWithACL, which interpolates usernames into SQL LIKE patterns without escaping the _ and % wildcards. Self-registered attackers can use usernames such as ___ or %%% that over-match ACL tokens, reading pages and Bazar entries restricted to other users or groups via the public Bazar listing API.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_