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CVE-2026-62959 (GCVE-0-2026-62959)

Vulnerability from cvelistv5 – Published: 2026-07-31 19:57 – Updated: 2026-07-31 23:34
VLAI
Title
Coturn: Pre-authentication heap memory disclosure in ACME redirect (`try_acme_redirect`)
Summary
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.
Severity
8.2 (High)
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
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-31 23:34 UTC
CWE
  • CWE-125 - Out-of-bounds Read
  • CWE-195 - Signed to Unsigned Conversion Error
Assigner
References
Impacted products
Vendor Product Version CPE status
coturn coturn Affected: >= 4.5.2, < 4.15.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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