CVE-2026-102927: Input Validation Flaw

Description

HedgeDoc is an open source, real-time collaborative markdown notes application. Prior to 1.11.1, the WebSocket permission handler allows a note owner to store strings outside the supported freely, editable, limited, locked, protected, and private permission values. The viewing and editing checks handle only known values and can otherwise fall through to permissive behavior, making a note readable or writable more broadly than intended. SQLite deployments can persist the invalid value because the database column does not strictly enforce the set, while MySQL and PostgreSQL reject the database update but can leave the in-memory note state inconsistent for connected users until reload or cache eviction. Exploitation requires the note owner to intentionally submit an invalid permission value, and the owner could already choose a legitimate permissive setting, which limits the practical security impact. This issue is fixed in version 1.11.1.

Is your site exposed to CVE-2026-102927?

Run a free security scan — no signup, results in seconds.

EPSS — Exploit Prediction

0.0032

Probability of exploitation

0.25%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-20 Improper Input Validation

CWE-284 CWE-284

References

Other References

https://github.com/hedgedoc/hedgedoc/commit/0dda149c7f528a7e98a34a8459b7afb23c90a05b https://github.com/hedgedoc/hedgedoc/releases/tag/1.11.1 https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-93w7-49m2-cqwg

Frequently Asked Questions

What is CVE-2026-102927? +

HedgeDoc is an open source, real-time collaborative markdown notes application. Prior to 1.11.1, the WebSocket permission handler allows a note owner to store strings outside the supported freely, editable, limited, locked, protected, and private permission values. The viewing and editing checks handle only known values and can otherwise fall through to permissive behavior, making a note readable or writable more broadly than intended. SQLite deployments can persist the invalid value because the database column does not strictly enforce the set, while MySQL and PostgreSQL reject the database update but can leave the in-memory note state inconsistent for connected users until reload or cache eviction. Exploitation requires the note owner to intentionally submit an invalid permission value, and the owner could already choose a legitimate permissive setting, which limits the practical security impact. This issue is fixed in version 1.11.1.

How do I check if I'm vulnerable to CVE-2026-102927? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-13826

Zervit's portable HTTP/web server is vulnerable to remote DoS attacks when a configuration reset request is made. The vulnerability is …

CVE-2026-62658

A security flaw was discovered in certain NETGEAR Nighthawk RAX series routers that could allow someone already logged in to …

CVE-2024-54011

Penetration Testing engineers at Amazon have discovered a flaw where the camera system fails to properly handle data supplied in …

CVE-2026-56349

n8n before version 2.10.0 contains an input validation vulnerability in the Guardrail node that allows attackers to bypass default guardrail …

CVE-2026-6409

A Denial of Service (DoS) vulnerability exists in the Protobuf PHP library during the parsing of untrusted input. Maliciously structured …

CVE-2026-59650

In Bouncy Castle for Java before 1.85, MTI/A0 DH agreement exponentiates unvalidated peer value. This issue also affects Bouncy Castle …

CVE-2026-102927