CVE-2026-55523 in PraisonAI
Summary
by MITRE • 08/05/2026
PraisonAI is a multi-agent teams system. In versions 1.5.128 through 1.6.57, the praisonaiagents.tools.web_crawl_tools.web_crawl() function is vulnerable to server-side request forgery. While it validates the initially supplied URL and blocks direct loopback and private destinations, its default httpx fallback uses httpx.Client(follow_redirects=True) and does not revalidate intermediate or final redirect targets. An attacker who can influence a URL passed to web_crawl(), directly or through an agent or tool workflow, can supply an attacker-controlled public URL that passes the initial host check and then redirects to loopback, private-network, or cloud metadata endpoints reachable from the host, with the redirected response body returned in the web_crawl() result. This constitutes an incomplete fix and patch bypass for the previously disclosed web_crawl SSRF class (GHSA-qq9r-63f6-v542 / CVE-2026-40160 and GHSA-8f4v-xfm9-3244), since the guard validates only the requested URL and not the destination actually fetched after redirection. This issue has been fixed in version 1.6.58.
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Analysis
by VulDB Data Team • 08/05/2026
The vulnerability in PraisonAI affects the web_crawl() function within versions 1.5.128 through 1.6.57, creating a server-side request forgery condition that represents a critical security flaw in the multi-agent teams system. This issue stems from incomplete input validation mechanisms that fail to properly secure against redirect-based attacks. The function initially validates the supplied URL and blocks direct loopback and private network destinations, but this protection proves insufficient when dealing with HTTP redirects that occur during the crawling process.
The technical flaw manifests through the function's default httpx fallback behavior which employs httpx.Client(follow_redirects=True) without revalidating intermediate or final redirect targets. This design creates a pathway where an attacker can provide an externally accessible URL that passes the initial validation checks but subsequently redirects to internal endpoints such as loopback addresses, private network destinations, or cloud metadata services reachable from the host system. The vulnerability essentially allows attackers to bypass the security controls by leveraging HTTP redirection mechanisms to reach targets that would otherwise be blocked.
The operational impact of this vulnerability is significant as it enables attackers to potentially access sensitive internal resources through the web_crawl() function. When an attacker supplies a URL that redirects to loopback addresses, private network endpoints, or cloud metadata services, the final response body gets returned in the web_crawl() result, effectively allowing information disclosure and potential further exploitation. This represents a complete bypass of the originally implemented safeguards, as the system only validates the initial requested URL rather than the ultimate destination reached after following all redirects.
This vulnerability aligns with CWE-918 Server-Side Request Forgery (SSRF) and follows patterns identified in previous SSRF incidents such as GHSA-qq9r-63f6-v542 and CVE-2026-40160. The flaw demonstrates the common pattern where security controls are applied only to the initial request rather than accounting for the complete request lifecycle including redirects, which is a well-documented weakness in many web applications. The issue specifically relates to ATT&CK technique T1592.001 Discovery: Network Trust Dependencies and T1592.004 Discovery: Remote Data Collection.
The fix implemented in version 1.6.58 addresses this by ensuring that all redirect targets are properly validated, not just the initial URL. This comprehensive approach prevents attackers from exploiting the redirect mechanism to reach blocked destinations, thus resolving the incomplete protection that existed in earlier versions. The mitigation strategy requires revalidation of all intermediate and final redirect targets, implementing proper host validation throughout the entire request chain rather than relying solely on initial input sanitization.