CVE-2026-71231

CRITICAL
Published Aug 5, 2026 Modified Aug 5, 2026 CWE-89

Description

IOTSmartHome's gui/login.php checkCookie() function builds an authentication query as SELECT * FROM users WHERE ID='<decoded lastLogin cookie>' after base64-decoding the client-supplied lastLogin cookie via safe_decode(), which performs URL-safe base64 decoding with no sanitization of the decoded value before it is concatenated into the SQL string. An unauthenticated attacker can set a lastLogin cookie containing a base64-encoded SQL injection payload (e.g. base64("' OR '1'='1")) to bypass authentication and, via UNION-based injection, extract arbitrary data including user credentials.

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CVSS v3.1 Score

9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0036
Probability of exploitation
0.29%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-89 SQL Injection

References

Frequently Asked Questions

What is CVE-2026-71231? +
IOTSmartHome's gui/login.php checkCookie() function builds an authentication query as SELECT * FROM users WHERE ID='<decoded lastLogin cookie>' after base64-decoding the client-supplied lastLogin cookie via safe_decode(), which performs URL-safe base64 decoding with no sanitization of the decoded value before it is concatenated into the SQL string. An unauthenticated attacker can set a lastLogin cookie containing a base64-encoded SQL injection payload (e.g. base64("' OR '1'='1")) to bypass authentication and, via UNION-based injection, extract arbitrary data including user credentials. It has a CVSS v3.1 base score of 9.8 (CRITICAL).
How severe is CVE-2026-71231? +
CVE-2026-71231 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately. The EPSS score is 0.0036, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-71231? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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