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TI-2026-48302 Aliases CVE-2026-68553

Coturn: Format String Injection via TURN USERNAME/REALM into hiredis Redis Command

Priority MEDIUM 64CWE-134Published · Updated

Key facts

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

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.13.0, an authenticated TURN user can place printf-style format specifiers in the STUN USERNAME or REALM attribute, which passes is_secure_string() validation and is embedded into Redis keys at nine call sites in src/apps/relay/ns_ioalib_engine_impl.c. send_message_to_redis() in src/apps/relay/hiredis_libevent2.c then passes the attacker-controlled key as the format argument to redisAsyncCommand() while supplying only one variadic value, causing hiredis redisvFormatCommand() to read past the va_list. Exploitation can crash the coturn process and terminate active TURN sessions or disclose stack memory into Redis. This issue is fixed in version 4.13.0.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.0048 41st percentileScored 2026-11-07
Fix Fixed coturn (coturn): 4.13.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
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
coturncoturnbefore 4.13.04.13.0Patch availableCNA
  • coturn Vendorcoturn Affected before 4.13.0 Fixed in 4.13.0 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 4.13.0

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-2026-68553

References

Other 3

  • TI-2026-32037 Coturn: Stack buffer overflow in decode_oauth_token_gcm() CVSS 3.1CRITICAL 9.8
  • TI-2026-44985 Coturn: Pre-authentication heap memory disclosure in ACME redirect (`try_acme_redirect`) CVSS 4.0HIGH 8.2
  • 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
See all 26 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences