CVE-2026-56835: Auth Bypass (CVSS 8.3)

Description

PraisonAI is a multi-agent teams system. From version 3.11.0 to before version 4.6.59, PraisonAI's Slack bot applies its configured allowed_users, allowed_channels, and unknown-user pairing policy in the normal Slack message event handler, but not in the adjacent Slack app_mention event handler. A Slack workspace user who can mention the bot in a channel where the Slack app is present can trigger the configured PraisonAI agent even when: the sender is not in BotConfig.allowed_users; the channel is not in BotConfig.allowed_channels; unknown_user_policy="deny" is configured; and the same event content is correctly dropped by the normal message handler. This issue has been patched in version 4.6.59.

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CVSS v3.1 Score

8.3

HIGH

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

EPSS — Exploit Prediction

0.0022

Probability of exploitation

0.12%

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-862 Missing Authorization

CWE-863 Incorrect Authorization

References

Other References

https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-qvpf-j64c-jmhr https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-qvpf-j64c-jmhr

Frequently Asked Questions

What is CVE-2026-56835? +

PraisonAI is a multi-agent teams system. From version 3.11.0 to before version 4.6.59, PraisonAI's Slack bot applies its configured allowed_users, allowed_channels, and unknown-user pairing policy in the normal Slack message event handler, but not in the adjacent Slack app_mention event handler. A Slack workspace user who can mention the bot in a channel where the Slack app is present can trigger the configured PraisonAI agent even when: the sender is not in BotConfig.allowed_users; the channel is not in BotConfig.allowed_channels; unknown_user_policy="deny" is configured; and the same event content is correctly dropped by the normal message handler. This issue has been patched in version 4.6.59. It has a CVSS v3.1 base score of 8.3 (HIGH).

How severe is CVE-2026-56835? +

CVE-2026-56835 has a CVSS v3.1 score of 8.3 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0022, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-56835? +

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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