PYSEC-2026-3904

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Import Source
https://github.com/pypa/advisory-database/blob/main/vulns/praisonaiagents/PYSEC-2026-3904.yaml
JSON Data
https://api.osv.dev/v1/vulns/PYSEC-2026-3904
Aliases
Published
2026-09-10T09:44:54Z
Modified
2026-09-10T12:15:11Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N CVSS Calculator
Summary
praisonaiagents vulnerable to SSRF in web_crawl tool via redirect-following and DNS rebinding (validate-then-fetch gap)
Details

The web_crawl tool performs its SSRF check only on the initial URL: it resolves the hostname once with socket.gethostbyname and rejects private/loopback/link-local results. It then passes the URL to a fetcher that uses httpx.Client(follow_redirects=True) - or urllib.request.urlopen when httpx is absent, which also follows redirects - and re-resolves the hostname at connect time, with no further validation. This validate-here/fetch-there gap is bypassable two independent ways: HTTP redirects and DNS rebinding.

Affected code: src/praisonai-agents/praisonaiagents/tools/web_crawl_tools.py

  • Single-shot validation (lines 229-238): if os.environ.get("ALLOW_LOCAL_CRAWL") != "true": ip_str = socket.gethostbyname(hostname) # resolved ONCE, at validation time ip = ipaddress.ip_address(ip_str) if ip.is_loopback or ip.is_private or ip.is_link_local or ip.is_multicast or ip.is_unspecified: continue # rejected url_list.append(u)
  • Vulnerable fetch (_crawl_with_httpx, lines 142 / 149): follows redirects, re-resolves DNS, no re-check: with httpx.Client(follow_redirects=True, timeout=30.0) as client: response = client.get(url)

    fallback: urllib.request.urlopen(url, timeout=30) (also follows redirects by default)

  • web_crawl / crawl_web are registered tools (tools/init.py:156-157); httpx is the default fallback provider (dispatch at web_crawl_tools.py:269).

The two bypasses:

  1. Redirect: validation approves an attacker domain resolving to a public IP; attacker server replies 302 Location: http://169.254.169.254/... (or any internal host); the fetcher follows it unchecked.
  2. DNS rebinding (TOCTOU): validator's gethostbyname and fetcher's connect-time resolution are independent; a low-TTL attacker domain answers public to the validator and private/loopback to fetch.

Impact: An agent with web_crawl - driven by direct input or indirect prompt injection - can be made to read internal-only HTTP services and cloud instance-metadata endpoints (e.g. IAM credentials), with the response body returned in the tool output. Scope is Changed because the request pivots into the internal network.

Proof of concept: A PoC drives the real web_crawl() (httpx absent -> genuine urllib fallback). It runs a loopback "internal metadata" service and a loopback attacker redirector, substituting DNS only to stand in for "attacker owns a public domain" / offline routing - the redirect-following and connect-time re-resolution are the repo's own behavior. Observed: CONTROL: web_crawl("http://127.0.0.1:.../meta-data/") -> blocked (validator works) PoC 1A (redirect): attacker.example approved (public); 302 -> loopback metadata -> result.content leaks {"AccessKeyId":"ASIA_FAKE_STOLEN_CREDENTIAL_..."} PoC 1B (rebinding): gethostbyname(rebind.example)->public (allowed); connect->127.0.0.1 -> same secret leaked The control proves the validator blocks a direct loopback request, so the bypasses are genuine.

Remediation: Resolve the hostname once, validate that IP, and connect to that exact validated IP (pin it) rather than re-resolving. Disable redirect following (follow_redirects=False; for urllib use a redirect handler that re-validates), or re-validate every redirect hop's resolved IP. Apply the deny check to both the validator and the actual socket target. file_tools.py:364 already uses follow_redirects=False and is the correct pattern to propagate.

Distinct from prior advisories: The accepted SSRF advisories concern host-string parsing in different code — alternate loopback encodings in spider_tools (GHSA-5c6w-wwfq-7qqm) and the CLI @url feature (GHSA-5cxw-77wg-jrf3). This is in the web_crawl tool, which neither advisory names, and the mechanisms (redirect-following and DNS rebinding) differ categorically from host-string encoding; the spider_tools _host_is_blocked hardening does not apply to this tool.

References

Affected packages

PyPI / praisonaiagents

Package

Name
praisonaiagents
View open source insights on deps.dev
Purl
pkg:pypi/praisonaiagents

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.6.58

Affected versions

0.*
0.0.1
0.0.2
0.0.3
0.0.4
0.0.5
0.0.6
0.0.7
0.0.8
0.0.9
0.0.10
0.0.11
0.0.12
0.0.13
0.0.14
0.0.15
0.0.16
0.0.17
0.0.18
0.0.19
0.0.20
0.0.21
0.0.22
0.0.23
0.0.24
0.0.25
0.0.26
0.0.27
0.0.28
0.0.29
0.0.30
0.0.31
0.0.32
0.0.33
0.0.34
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0.0.36
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0.0.41
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0.0.43
0.0.44
0.0.45
0.0.46
0.0.47
0.0.48
0.0.49
0.0.50
0.0.51
0.0.52
0.0.53
0.0.54
0.0.56
0.0.57
0.0.58
0.0.59
0.0.60
0.0.61
0.0.62
0.0.63
0.0.64
0.0.65
0.0.66
0.0.67
0.0.68
0.0.69
0.0.70
0.0.71
0.0.72
0.0.73
0.0.74
0.0.75
0.0.76
0.0.77
0.0.78
0.0.79
0.0.80
0.0.81
0.0.82
0.0.83
0.0.84
0.0.85
0.0.86
0.0.87
0.0.88
0.0.89
0.0.90
0.0.91
0.0.92
0.0.93
0.0.94
0.0.95
0.0.96
0.0.97
0.0.98
0.0.99
0.0.100
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0.0.103
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0.0.175
0.0.176
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0.0.184
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0.0.190
0.0.191
0.0.192
0.0.193
0.0.194
0.0.195
0.0.196
0.0.197
0.0.198
0.0.199
0.1.0
0.1.1
0.1.2
0.1.3
0.1.4
0.1.5
0.1.6
0.1.7
0.1.8
0.1.9
0.1.10
0.1.11
0.1.12
0.1.13
0.1.14
0.1.15
0.1.16
0.1.17
0.1.18
0.1.19
0.1.20
0.1.21
0.1.22
0.1.23
0.1.24
0.1.25
0.1.26
0.1.27
0.2.0
0.2.1
0.2.2
0.3.0
0.3.1
0.3.2
0.3.3
0.3.4
0.4.0
0.4.1
0.5.0
0.5.1
0.5.2
0.5.3
0.6.0
0.6.1
0.6.2
0.6.3
0.6.4
0.6.5
0.6.6
0.6.7
0.6.8
0.7.0
0.7.1
0.8.0
0.8.1
0.9.0
0.9.1
0.10.0
0.10.1
0.10.2
0.10.3
0.10.4
0.10.5
0.10.6
0.10.7
0.10.8
0.10.9
0.10.10
0.11.0
0.11.1
0.11.2
0.11.3
0.11.4
0.11.5
0.11.6
0.11.7
0.11.8
0.11.9
0.11.10
0.11.11
0.11.12
0.11.13
0.11.14
0.11.15
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0.11.17
0.11.18
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0.11.24
0.11.25
0.11.27
0.11.28
0.11.29
0.11.30
0.11.31
0.12.0
0.12.1
0.12.2
0.12.3
0.12.4
0.12.5
0.12.6
0.12.7
0.12.8
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0.12.17
0.12.18
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0.12.21
0.13.0
0.13.1
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0.13.3
0.13.4
0.13.5
0.13.6
0.13.7
0.13.8
0.13.9
0.13.10
0.13.11
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0.13.16
0.13.17
0.13.18
0.13.19
0.13.20
0.13.21
0.13.22
0.13.23
0.14.0
0.14.1
0.14.2
0.14.3
0.14.4
0.14.5
0.14.6
0.14.7
0.14.8
0.14.9
0.14.10
0.14.11
0.14.12
0.14.14
0.14.15
0.14.16
0.15.0
0.15.1
0.15.2
0.15.3
1.*
1.0.0
1.1.0
1.2.0
1.2.1
1.2.2
1.2.3
1.2.4
1.3.0
1.3.1
1.4.0
1.4.1
1.4.2
1.4.3
1.4.4
1.4.5
1.4.6
1.4.7
1.4.8
1.5.0
1.5.1
1.5.2
1.5.3
1.5.5
1.5.6
1.5.7
1.5.8
1.5.9
1.5.10
1.5.11
1.5.12
1.5.13
1.5.14
1.5.15
1.5.16
1.5.17
1.5.18
1.5.19
1.5.20
1.5.21
1.5.22
1.5.23
1.5.24
1.5.25
1.5.26
1.5.27
1.5.28
1.5.29
1.5.30
1.5.31
1.5.32
1.5.33
1.5.34
1.5.35
1.5.36
1.5.37
1.5.38
1.5.39
1.5.40
1.5.41
1.5.42
1.5.43
1.5.44
1.5.45
1.5.46
1.5.47
1.5.48
1.5.49
1.5.50
1.5.51
1.5.52
1.5.53
1.5.54
1.5.55
1.5.56
1.5.57
1.5.58
1.5.59
1.5.60
1.5.61
1.5.62
1.5.63
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1.5.65
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1.5.67
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1.5.69
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1.5.73
1.5.74
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1.5.80
1.5.81
1.5.82
1.5.83
1.5.84
1.5.85
1.5.86
1.5.87
1.5.88
1.5.89
1.5.90
1.5.91
1.5.92
1.5.93
1.5.94
1.5.95
1.5.96
1.5.97
1.5.98
1.5.99
1.5.100
1.5.101
1.5.102
1.5.103
1.5.104
1.5.105
1.5.106
1.5.107
1.5.108
1.5.109
1.5.110
1.5.111
1.5.112
1.5.113
1.5.114
1.5.115
1.5.116
1.5.117
1.5.118
1.5.119
1.5.120
1.5.121
1.5.122
1.5.123
1.5.124
1.5.125
1.5.126
1.5.127
1.5.128
1.5.129
1.5.130
1.5.131
1.5.132
1.5.133
1.5.134
1.5.135
1.5.136
1.5.137
1.5.138
1.5.139
1.5.140
1.5.141
1.5.142
1.5.143
1.5.144
1.5.145
1.5.146
1.5.147
1.5.148
1.5.149
1.6.1
1.6.2
1.6.3
1.6.4
1.6.5
1.6.6
1.6.7
1.6.8
1.6.9
1.6.10
1.6.11
1.6.12
1.6.13
1.6.14
1.6.15
1.6.16
1.6.17
1.6.18
1.6.19
1.6.20
1.6.21
1.6.22
1.6.23
1.6.24
1.6.25
1.6.26
1.6.27
1.6.28
1.6.29
1.6.30
1.6.31
1.6.32
1.6.33
1.6.34
1.6.35
1.6.36
1.6.37
1.6.38
1.6.39
1.6.40
1.6.41
1.6.42
1.6.43
1.6.44
1.6.45
1.6.46
1.6.47
1.6.48
1.6.50
1.6.51
1.6.52
1.6.53
1.6.54
1.6.55
1.6.56
1.6.57

Database specific

source 
"https://github.com/pypa/advisory-database/blob/main/vulns/praisonaiagents/PYSEC-2026-3904.yaml"