CVE-2026-52771 is a high-severity (CVSS 8.3) SQL Injection vulnerability in yeswiki/yeswiki. A fix is available for yeswiki/yeswiki — see the affected versions and patch details below.
YesWiki: Second-Order SQL Injection in Page Delete API via Unescaped Page Tag (`ApiController::deletePage`)
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-52771.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-52771 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
yeswiki/yeswikiReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
YesWiki is a wiki system written in PHP. From version 4.2.0 to before version 4.6.6, ApiController::deletePage() interpolates a page tag retrieved from the database into a DELETE FROM …_links WHERE to_tag = '$tag' query without escaping. The page tag is attacker-controlled — the POST /api/pages/{tag} API accepts arbitrary URL-encoded values, including single quotes, and stores them. A low-privilege authenticated user can therefore create a page whose tag is a SQL fragment, make the page non-orphaned via the standard {{include page="…"}} link mechanism, and then invoke the delete endpoint to execute arbitrary SQL inside the wiki database - including time-based blind data exfiltration from any table. This issue has been patched in version 4.6.6.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | yeswiki/yeswiki | ≥ 4.2.0&&< 4.6.6 | 4.6.6composer require yeswiki/yeswiki:^4.6.6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for yeswiki/yeswiki, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update yeswiki/yeswiki to 4.6.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-52771 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-52771 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-52771. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-52771 in your dependencies?
O3 Security finds CVE-2026-52771 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.