CVE-2026-55526

PraisonAI is a multi-agent teams system. Prior to praisonaiagents 1.6.58, spider_tools._host_is_blocked() does not resolve ordinary hostnames before scrape_page fetches them. A hostname such as 127.0.0.1.nip.io passes validation and resolves to loopback, permitting internal HTTP access. The fix uses socket.getaddrinfo and fails closed on DNS errors. This issue is fixed in version 1.6.58.

PraisonAI is a multi-agent teams system. Prior to praisonaiagents 1.6.58, spider_tools._host_is_blocked() does not resolve ordinary hostnames before scrape_page fetches them. A hostname such as 127.0.0.1.nip.io passes validation and resolves to loopback, permitting internal HTTP access. The fix uses socket.getaddrinfo and fails closed on DNS errors. This issue is fixed in version 1.6.58.

Summary

praisonaiagents/tools/spider_tools.py contains an SSRF protection bypass. The function _host_is_blocked() validates URLs against a list of blocked IP literals and hostname aliases, but never performs DNS resolution. Any hostname that resolves to a private or loopback IP address — including public wildcard DNS services like 127.0.0.1.nip.io — bypasses the protection entirely.

This has been confirmed with a live exploit: scrape_page("http://127.0.0.1.nip.io:PORT/secret") makes an HTTP request to 127.0.0.1:PORT and returns the internal service response. No attacker-controlled infrastructure is required.

scrape_page, extract_links, crawl, and extract_text are all registered as LLM-callable agent tools (see tools/__init__.py lines 51-55), so any agent instructed to fetch a user-supplied URL will trigger this path.

This is a new bypass of prior fix commit 004dcfef (GHSA-q9pw-vmhh-384g), which only rejected IP literal encoding tricks (hex, octal, backslash). The fix was also applied to web_crawl_tools.py (line 231: socket.gethostbyname call), but that fix was not ported to spider_tools.py.

Details

Root cause — spider_tools.py lines 26-65:

def _host_is_blocked(hostname: str) -> bool:
    host = hostname.lower().rstrip(".")
    # Checks literal aliases only — never resolves
    if host in ("localhost", "0.0.0.0", "::1"):
        return True
    if host in ("169.254.169.254", "metadata.google.internal"):
        return True
    if any(host.endswith(s) for s in (".local", ".internal", ".localdomain")):
        return True
    # Tries to parse as IP literal only
    try:
        return _ip_blocked(ipaddress.ip_address(host))
    except ValueError:
        pass
    try:
        return _ip_blocked(ipaddress.ip_address(socket.inet_aton(host)))
    except OSError:
        pass
    return False   # <-- ANY real hostname passes without DNS lookup

socket.inet_aton() only converts dotted-decimal strings, not hostnames. For any real hostname (e.g. 127.0.0.1.nip.io), both ipaddress.ip_address() and socket.inet_aton() raise exceptions, and the function returns False (not blocked).

Contrast with the fixed version in web_crawl_tools.py line 228-238:

if os.environ.get("ALLOW_LOCAL_CRAWL") != "true":
    try:
        ip_str = socket.gethostbyname(hostname)   # DNS resolution performed
        ip = ipaddress.ip_address(ip_str)
        if ip.is_loopback or ip.is_private or ip.is_link_local or ip.is_multicast:
            continue  # BLOCKED
    except socket.gaierror:
        continue  # fail-closed

Tool registration confirms this is user-reachable:

# praisonaiagents/tools/__init__.py lines 51-55
TOOL_MAPPINGS = {
    'scrape_page':   ('.spider_tools', None),  # <- user-reachable LLM tool
    'extract_links': ('.spider_tools', None),
    'crawl':         ('.spider_tools', None),
    'extract_text':  ('.spider_tools', None),
    ...
}

Any agent given these tools will call scrape_page(url) when instructed to fetch a user-supplied URL — including attacker-controlled ones.

PoC

Environment: Python 3.x, praisonaiagents <= 1.6.52, internet access (for nip.io)

Step 1 — Verify the filter bypass (no network needed):

from praisonaiagents.tools.spider_tools import SpiderTools, _host_is_blocked

# nip.io: public wildcard DNS — 127.0.0.1.nip.io always resolves to 127.0.0.1
print(_host_is_blocked("127.0.0.1.nip.io"))                        # False — NOT blocked
print(SpiderTools()._validate_url("http://127.0.0.1.nip.io/"))      # True  — ALLOWED
print(_host_is_blocked("127.0.0.1"))                                # True  — correctly blocked

Expected output:

False
True
True

Step 2 — Full SSRF: internal service response exfiltrated

import threading, time, requests
from http.server import HTTPServer, BaseHTTPRequestHandler
from…

PraisonAI is a multi-agent teams system. Prior to praisonaiagents 1.6.58, spider_tools._host_is_blocked() does not resolve ordinary hostnames before scrape_page fetches them. A hostname such as 127.0.0.1.nip.io passes validation and resolves to loopback, permitting internal HTTP access. The fix uses socket.getaddrinfo and fails closed on DNS errors. This issue is fixed in version 1.6.58.

PraisonAI is a multi-agent teams system. Prior to praisonaiagents 1.6.58, spider_tools._host_is_blocked() does not resolve ordinary hostnames before scrape_page fetches them. A hostname such as 127.0.0.1.nip.io passes validation and resolves to loopback, permitting internal HTTP access. The fix uses socket.getaddrinfo and fails closed on DNS errors. This issue is fixed in version 1.6.58.

Summary

praisonaiagents/tools/spider_tools.py contains an SSRF protection bypass. The function _host_is_blocked() validates URLs against a list of blocked IP literals and hostname aliases, but never performs DNS resolution. Any hostname that resolves to a private or loopback IP address — including public wildcard DNS services like 127.0.0.1.nip.io — bypasses the protection entirely.

This has been confirmed with a live exploit: scrape_page("http://127.0.0.1.nip.io:PORT/secret") makes an HTTP request to 127.0.0.1:PORT and returns the internal service response. No attacker-controlled infrastructure is required.

scrape_page, extract_links, crawl, and extract_text are all registered as LLM-callable agent tools (see tools/__init__.py lines 51-55), so any agent instructed to fetch a user-supplied URL will trigger this path.

This is a new bypass of prior fix commit 004dcfef (GHSA-q9pw-vmhh-384g), which only rejected IP literal encoding tricks (hex, octal, backslash). The fix was also applied to web_crawl_tools.py (line 231: socket.gethostbyname call), but that fix was not ported to spider_tools.py.

Details

Root cause — spider_tools.py lines 26-65:

def _host_is_blocked(hostname: str) -> bool:
    host = hostname.lower().rstrip(".")
    # Checks literal aliases only — never resolves
    if host in ("localhost", "0.0.0.0", "::1"):
        return True
    if host in ("169.254.169.254", "metadata.google.internal"):
        return True
    if any(host.endswith(s) for s in (".local", ".internal", ".localdomain")):
        return True
    # Tries to parse as IP literal only
    try:
        return _ip_blocked(ipaddress.ip_address(host))
    except ValueError:
        pass
    try:
        return _ip_blocked(ipaddress.ip_address(socket.inet_aton(host)))
    except OSError:
        pass
    return False   # <-- ANY real hostname passes without DNS lookup

socket.inet_aton() only converts dotted-decimal strings, not hostnames. For any real hostname (e.g. 127.0.0.1.nip.io), both ipaddress.ip_address() and socket.inet_aton() raise exceptions, and the function returns False (not blocked).

Contrast with the fixed version in web_crawl_tools.py line 228-238:

if os.environ.get("ALLOW_LOCAL_CRAWL") != "true":
    try:
        ip_str = socket.gethostbyname(hostname)   # DNS resolution performed
        ip = ipaddress.ip_address(ip_str)
        if ip.is_loopback or ip.is_private or ip.is_link_local or ip.is_multicast:
            continue  # BLOCKED
    except socket.gaierror:
        continue  # fail-closed

Tool registration confirms this is user-reachable:

# praisonaiagents/tools/__init__.py lines 51-55
TOOL_MAPPINGS = {
    'scrape_page':   ('.spider_tools', None),  # <- user-reachable LLM tool
    'extract_links': ('.spider_tools', None),
    'crawl':         ('.spider_tools', None),
    'extract_text':  ('.spider_tools', None),
    ...
}

Any agent given these tools will call scrape_page(url) when instructed to fetch a user-supplied URL — including attacker-controlled ones.

PoC

Environment: Python 3.x, praisonaiagents <= 1.6.52, internet access (for nip.io)

Step 1 — Verify the filter bypass (no network needed):

from praisonaiagents.tools.spider_tools import SpiderTools, _host_is_blocked

# nip.io: public wildcard DNS — 127.0.0.1.nip.io always resolves to 127.0.0.1
print(_host_is_blocked("127.0.0.1.nip.io"))                        # False — NOT blocked
print(SpiderTools()._validate_url("http://127.0.0.1.nip.io/"))      # True  — ALLOWED
print(_host_is_blocked("127.0.0.1"))                                # True  — correctly blocked

Expected output:

False
True
True

Step 2 — Full SSRF: internal service response exfiltrated

import threading, time, requests
from http.server import HTTPServer, BaseHTTPRequestHandler
from…

Summary

praisonaiagents/tools/spider_tools.py contains an SSRF protection bypass. The function _host_is_blocked() validates URLs against a list of blocked IP literals and hostname aliases, but never performs DNS resolution. Any hostname that resolves to a private or loopback IP address — including public wildcard DNS services like 127.0.0.1.nip.io — bypasses the protection entirely.

This has been confirmed with a live exploit: scrape_page("http://127.0.0.1.nip.io:PORT/secret") makes an HTTP request to 127.0.0.1:PORT and returns the internal service response. No attacker-controlled infrastructure is required.

scrape_page, extract_links, crawl, and extract_text are all registered as LLM-callable agent tools (see tools/__init__.py lines 51-55), so any agent instructed to fetch a user-supplied URL will trigger this path.

This is a new bypass of prior fix commit 004dcfef (GHSA-q9pw-vmhh-384g), which only rejected IP literal encoding tricks (hex, octal, backslash). The fix was also applied to web_crawl_tools.py (line 231: socket.gethostbyname call), but that fix was not ported to spider_tools.py.

Details

Root cause — spider_tools.py lines 26-65:

def _host_is_blocked(hostname: str) -> bool:
    host = hostname.lower().rstrip(".")
    # Checks literal aliases only — never resolves
    if host in ("localhost", "0.0.0.0", "::1"):
        return True
    if host in ("169.254.169.254", "metadata.google.internal"):
        return True
    if any(host.endswith(s) for s in (".local", ".internal", ".localdomain")):
        return True
    # Tries to parse as IP literal only
    try:
        return _ip_blocked(ipaddress.ip_address(host))
    except ValueError:
        pass
    try:
        return _ip_blocked(ipaddress.ip_address(socket.inet_aton(host)))
    except OSError:
        pass
    return False   # <-- ANY real hostname passes without DNS lookup

socket.inet_aton() only converts dotted-decimal strings, not hostnames. For any real hostname (e.g. 127.0.0.1.nip.io), both ipaddress.ip_address() and socket.inet_aton() raise exceptions, and the function returns False (not blocked).

Contrast with the fixed version in web_crawl_tools.py line 228-238:

if os.environ.get("ALLOW_LOCAL_CRAWL") != "true":
    try:
        ip_str = socket.gethostbyname(hostname)   # DNS resolution performed
        ip = ipaddress.ip_address(ip_str)
        if ip.is_loopback or ip.is_private or ip.is_link_local or ip.is_multicast:
            continue  # BLOCKED
    except socket.gaierror:
        continue  # fail-closed

Tool registration confirms this is user-reachable:

# praisonaiagents/tools/__init__.py lines 51-55
TOOL_MAPPINGS = {
    'scrape_page':   ('.spider_tools', None),  # <- user-reachable LLM tool
    'extract_links': ('.spider_tools', None),
    'crawl':         ('.spider_tools', None),
    'extract_text':  ('.spider_tools', None),
    ...
}

Any agent given these tools will call scrape_page(url) when instructed to fetch a user-supplied URL — including attacker-controlled ones.

PoC

Environment: Python 3.x, praisonaiagents <= 1.6.52, internet access (for nip.io)

Step 1 — Verify the filter bypass (no network needed):

from praisonaiagents.tools.spider_tools import SpiderTools, _host_is_blocked

# nip.io: public wildcard DNS — 127.0.0.1.nip.io always resolves to 127.0.0.1
print(_host_is_blocked("127.0.0.1.nip.io"))                        # False — NOT blocked
print(SpiderTools()._validate_url("http://127.0.0.1.nip.io/"))      # True  — ALLOWED
print(_host_is_blocked("127.0.0.1"))                                # True  — correctly blocked

Expected output:

False
True
True

Step 2 — Full SSRF: internal service response exfiltrated

import threading, time, requests
from http.server import HTTPServer, BaseHTTPRequestHandler
from…