CVE-2026-111675 xiaochong0302 CVE debrief

Who should care

Defenders responsible for Course-tencent-cloud installations, security teams monitoring for authentication bypass vulnerabilities, administrators of affected systems, and operators of platforms using Course-tencent-cloud should prioritize verifying and remediating affected installations to prevent exploitation. Security teams should review compensating controls for exposed systems while remediation is scheduled and verified. Vulnerability management teams

Why it matters

CVE-2026-111675 is a critical vulnerability in Course-tencent-cloud that allows unauthenticated attackers to brute force verification codes, potentially leading to account takeover. Defenders should prioritize verifying and remediating affected installations to prevent exploitation.

• Unauthenticated attackers can brute force verification codes to gain unauthorized access to accounts
• Successful exploitation can lead to account takeover without requiring prior authentication
• Defenders must verify and remediate affected Course-tencent-cloud installations to prevent exploitation
• Implementing compensating controls such as IP blocking or rate limiting may be necessary

Technical summary

Course-tencent-cloud through 2.0.1 contains an improper restriction of authentication attempts vulnerability that allows unauthenticated attackers to brute force 6-digit SMS/email verification codes. This vulnerability can lead to account takeover if exploited. The vulnerability has a CVSS score of 9.1 and is considered critical. Affected systems include Course-tencent-cloud installations up to version 2.0.1. Defenders should prioritize verifying and remediating affected installations to prevent exploitation. Implementing compensating controls such as IP blocking or rate limiting may be necessary.

Defensive priority

Defenders should prioritize verifying and remediating affected Course-tencent-cloud installations.

Recommended defensive actions

• Verify Course-tencent-cloud installations for version 2.0.1 or earlier and plan for upgrades or mitigations.
• Implement rate limiting on verification code attempts to prevent brute force attacks.
• Monitor for suspicious login and password reset activity to detect potential exploitation.
• Consider upgrading to a version beyond 2.0.1 if available.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record and source item provide details on the improper restriction of authentication attempts vulnerability in Course-tencent-cloud through 2.0.1. The vulnerability allows unauthenticated attackers to brute force 6-digit SMS/email verification codes, which are never invalidated or attempt-limited. Attackers who know a victim's phone or email can trigger a code and rotate source IPs against the password reset and verify login endpoints to take over accounts. The source item provides additional context on the vulnerability, and

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.