Coturn is a free open source implementation of TURN and STUN Server. From 4.5.2 through 4.14.0, when Coturn is started with --acme-redirect <URL> and exposes a plaintext-TCP listener, an unauthenticated remote client can send a single ordinary HTTP GET request and receive a 301 response whose Location header contains up to ~870 bytes of adjacent process heap memory. The leaked region is a recycled network receive buffer that is reused without being zeroed, so on a busy server it can contain data from other clients' requests (TURN credentials, OAuth tokens, relayed payloads). Root cause is a signed→unsigned conversion. This issue is fixed in version 4.15.0.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

No CVSS v3.1

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
coturn coturn affected
Version Status Constraints
>= 4.5.2, < 4.15.0 affected —

No data.

No data.

OpenCVE Enrichment is a feature of OpenCVE that uses AI to automatically link vendors and products to CVEs. Learn more on GitHub.

Vendors Products
Coturn Subscribe
Coturn Subscribe

Project Subscriptions

Vendors Products
Coturn Subscribe
Coturn Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/coturn/coturn/commit/960835886692fa04cf63ddd970c3f330740c87f4 cve-icon
https://github.com/coturn/coturn/pull/1965 cve-icon
https://github.com/coturn/coturn/releases/tag/4.15.0 cve-icon
https://github.com/coturn/coturn/security/advisories/GHSA-m23x-5qf5-988g cve-icon
History

Fri, 31 Jul 2026 22:45:00 +0000

Type Values Removed Values Added
First Time appeared Coturn
Coturn coturn
Vendors & Products Coturn
Coturn coturn

Fri, 31 Jul 2026 20:15:00 +0000

Type Values Removed Values Added
Description Coturn is a free open source implementation of TURN and STUN Server. From 4.5.2 through 4.14.0, when Coturn is started with --acme-redirect <URL> and exposes a plaintext-TCP listener, an unauthenticated remote client can send a single ordinary HTTP GET request and receive a 301 response whose Location header contains up to ~870 bytes of adjacent process heap memory. The leaked region is a recycled network receive buffer that is reused without being zeroed, so on a busy server it can contain data from other clients' requests (TURN credentials, OAuth tokens, relayed payloads). Root cause is a signed→unsigned conversion. This issue is fixed in version 4.15.0.
Title Coturn: Pre-authentication heap memory disclosure in ACME redirect (`try_acme_redirect`)
Weaknesses CWE-125
CWE-195
References
Metrics cvssV4_0

{'score': 8.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}

Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-07-31T19:57:06.394Z

Reserved: 2026-07-14T22:32:17.732Z

Link: CVE-2026-62959

cve-icon Vulnrichment

No data.

cve-icon NVD

No data.

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-07-31T22:30:17Z

Weaknesses