# CVE-2026-116821: YesWiki before 4.7.0 Read-ACL Bypass via SQL LIKE Wildcards in Usernames

Status: published. Published: 2026-10-26. Updated: 2026-11-02.

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.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/YesWiki/yeswiki/commit/f3b0dd093a7ace47dc29a515faeb02635baceae2

## Affected products and versions

- YesWiki / yeswiki: ≥ 0; < 4.7.0 (affected, semver); 4.7.0 (unaffected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 7.1 (high); CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 6.5 (medium); CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: 0.28% as of 2026-11-02; percentile 20.35%

- SSVC: exploitation poc; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-89

## Exploit evidence

- exploit: https://github.com/YesWiki/yeswiki/security/advisories/GHSA-q5j6-79p7-mp94 (ADP: CISA-ADP)

## References

- https://github.com/YesWiki/yeswiki/security/advisories/GHSA-q5j6-79p7-mp94 (CNA: VulnCheck; vendor-advisory)

- https://github.com/YesWiki/yeswiki/commit/f3b0dd093a7ace47dc29a515faeb02635baceae2 (CNA: VulnCheck; patch)

- https://www.vulncheck.com/advisories/yeswiki-before-4.7.0-read-acl-bypass-via-sql-like-wildcards-in-usernames (CNA: VulnCheck; third-party-advisory)

- https://github.com/YesWiki/yeswiki/security/advisories/GHSA-q5j6-79p7-mp94 (ADP: CISA-ADP; exploit)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-116821; retrieved 2026-11-02; source updated 2026-11-02

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-116821; retrieved 2026-11-02; source updated Not reported

Revision: 23711e43c04089cfd63b4ff64feb3396ae3dfbf9658f430c56f7c427c16f65ea

Canonical: https://y2.dev/cve/CVE-2026-116821

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.