CVE-2026-77519

MEDIUM
Published Sep 21, 2026 Modified Sep 24, 2026 CWE-613

Description

MaxKB is an open-source AI assistant for enterprise. In 2.10.2-lts and earlier, the /chat/api/mcp authentication path looks up an ApplicationApiKey using only its secret and active status, without enforcing the is_permanent and expire_time checks used by the standard chat API. A previously valid, non-permanent application key that remains active after expiration can initialize the MCP endpoint, list the published application's tool metadata, invoke tools/call, and create durable application_chat and application_chat_record state even though /chat/api/open rejects the same key. No fixed version is available as of this review.

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CVSS v3.1 Score

5.4
MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

EPSS — Exploit Prediction

0.0024
Probability of exploitation
0.14%
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-613 CWE-613

References

Frequently Asked Questions

What is CVE-2026-77519? +
MaxKB is an open-source AI assistant for enterprise. In 2.10.2-lts and earlier, the /chat/api/mcp authentication path looks up an ApplicationApiKey using only its secret and active status, without enforcing the is_permanent and expire_time checks used by the standard chat API. A previously valid, non-permanent application key that remains active after expiration can initialize the MCP endpoint, list the published application's tool metadata, invoke tools/call, and create durable application_chat and application_chat_record state even though /chat/api/open rejects the same key. No fixed version is available as of this review. It has a CVSS v3.1 base score of 5.4 (MEDIUM).
How severe is CVE-2026-77519? +
CVE-2026-77519 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0024, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-77519? +
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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