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TI-2026-44985 Aliases CVE-2026-62959

Coturn: Pre-authentication heap memory disclosure in ACME redirect (`try_acme_redirect`)

Priority HIGH 75CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00524 44th percentileScored 2026-11-07
Fix Fixed coturn (coturn): 4.15.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
coturncoturn4.5.2 to before 4.15.04.15.0Patch availableCNA
  • coturn Vendorcoturn Affected 4.5.2 to before 4.15.0 Fixed in 4.15.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:coturn_project:coturn:*:*:*:*:*:*:*:*——coturn
  • cpe:2.3:a:coturn_project:coturn:*:*:*:*:*:*:*:* Versions — — ·coturn

Remediation

  • Fix · CNA coturn (coturn) Fixed in 4.15.0

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-62959

References

  • TI-2026-32037 Coturn: Stack buffer overflow in decode_oauth_token_gcm() CVSS 3.1CRITICAL 9.8
  • TI-2026-29348 Coturn: Misaligned Memory Access in coturn STUN Attribute Parser (Remote DoS on ARM64) CVSS 3.1HIGH 7.5
  • TI-2026-22006 Coturn: IPv4-mapped IPv6 (::ffff:0:0/96) bypasses denied-peer-ip ACL CVSS 3.1HIGH 7.2
  • TI-2026-38529 Coturn: SQL Injection in HTTPS Admin Panel Delete Operations CVSS 3.1HIGH 7.2
  • TI-2026-46994 Coturn: MOBILITY-TICKET session-resume authorization bypass allows cross-user TURN allocation takeover CVSS 3.1HIGH 7.1
  • TI-2026-38531 Coturn: IPv4-mapped 127.0.0.1 bypasses default loopback peer protection CVSS 3.1HIGH 7.4
See all 26 →

Sources