Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%
Buy Us a Coffee

CVE-2026-68553— Coturn: Format String Injection via TURN USERNAME/REALM into hiredis Redis Command

Quick assessment

Affected
coturn coturn
Exploitation
Public or AI PoC available; prioritize validation
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Coturn是Coturn组织开源的一款实现TURN协议的服务器软件。 Coturn 4.13.0之前版本存在格式化字符串错误漏洞，该漏洞源于STUN USERNAME或REALM属性中存在printf样式格式说明符，可能导致进程崩溃、终止活动TURN会话或将堆栈内存泄露到Redis。

CVSS 7.1 · High EPSS 0.28% · P20

Possible ATT&CK Techniques 1 AI

T1041 · Exfiltration Over C2 Channel

Affected Version Matrix 1

VendorProduct Version RangeStatus
coturn coturn < 4.13.0 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-68553

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Coturn: Format String Injection via TURN USERNAME/REALM into hiredis Redis Command
Source: CVE Program / CVE List V5
Vulnerability Description
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.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
使用外部控制的格式字符串
Source: CVE Program / CVE List V5
Vulnerability Title
Coturn 格式化字符串错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Coturn是Coturn组织开源的一款实现TURN协议的服务器软件。 Coturn 4.13.0之前版本存在格式化字符串错误漏洞，该漏洞源于STUN USERNAME或REALM属性中存在printf样式格式说明符，可能导致进程崩溃、终止活动TURN会话或将堆栈内存泄露到Redis。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
coturn coturn < 4.13.0 -

II. Public POCs for CVE-2026-68553

# POC Description Source Link Shenlong Link
AI-Generated POC Premium
Qwen3.6-35B-A3B · 9908 chars
Pro+ exclusive includes:
Vulnerability reproduction recording (real sandbox build + trigger, exclusive)
In-depth vulnerability mechanism
Trigger conditions & impact
Full executable POC code
Exploit chain & mitigation
POC zip download
100+ AI POC generations per month

III. Intelligence Information for CVE-2026-68553

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-68553 (1)

Vendor Advisories for CVE-2026-68553 (1)

Vendor Pages for CVE-2026-68553 (1)

Same Patch Batch · coturn · 2026-08-19 · 4 CVEs total

CVE-2026-68555 6.5 MEDIUM coturn: Chained mobility resumes allow authenticated remote memory exhaustion
CVE-2026-68552 5.3 MEDIUM Coturn: uint16_t truncation overflow in STUN message length causes TCP stream framing bypa
CVE-2026-68554 2.3 LOW Coturn: STUN attributes after MESSAGE-INTEGRITY are processed, letting on-path attackers m

IV. Related Vulnerabilities

Same product: coturn
Same vendor: coturn
Same weakness: CWE-134

V. Comments for CVE-2026-68553

No comments yet

Leave a comment