CVE WatchJul 31, 2026

CVE-2026-62959

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

CVSS

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No CVSS

EPSS

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KEV

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Exploit Today

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0-100

Published: Jul 31, 2026 · Last modified: Jul 31, 2026 · CWE-125 · CWE-195

EPSS · 30d

Not enough EPSS history yet.

Technical 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.

Official references

Related CVEs

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——0The GOOSE parser contains an off-by-one boundary-handling flaw that can be triggered by a single unauthenticated Layer-2 multicast frame on the process bus. When specific GOOSE message fields are processed, the parser advances its internal buffer position incorrectly, resulting in a heap out-of-bounds read. On affected platforms, this condition reliably terminates the subscriber process and causes a denial-of-service.9h CVE-2026-663646.5 MED

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——0The GOOSE payload parser contains a boundary handling flaw that can be triggered by a single unauthenticated Layer 2 multicast frame on the process bus. When processing specific payload fields, an attacker controlled inner element length may exceed its enclosing length, causing the parser to over read by one byte. This out-of-bounds read reliably terminates the subscriber process, resulting in a denial-of-service condition.13h CVE-2026-663607.5 HIG

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——0The MMS server connection handler contains a flaw in its processing of BER-encoded request data. When an MMS confirmed request PDU containing an extended BER tag is received over an established session, the decoder may advance its internal buffer incorrectly due to a missing bounds check. This results in a one byte heap out-of-bounds read and causes the MMS service process to terminate, leading to a denial-of-service condition.13h CVE-2026-654216.5 MED

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——0The MMS BER decoder contains a flaw in decoding fixed-width BER fields (boolean/integer): an attacker-supplied length value is not validated, causing a read past the end of a heap buffer. This leads to termination of the MMS service process and a denial-of-service condition.13h