benoitc hackney up to 4.8.99 URL Normalization hackney_url.normalize server-side request forgery

Summaryinfo

A vulnerability labeled as critical has been found in benoitc hackney up to 4.8.99. Affected is the function hackney_url.normalize of the component URL Normalization. Executing a manipulation can lead to server-side request forgery. This vulnerability is handled as CVE-2026-115700. The attack can be executed remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in benoitc hackney up to 4.8.99. It has been declared as critical. This vulnerability affects the function hackney_url.normalize of the component URL Normalization. The manipulation with an unknown input leads to a server-side request forgery vulnerability. The CWE definition for the vulnerability is CWE-918. The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Interpretation Conflict vulnerability in hackney_url in benoitc hackney allows Server Side Request Forgery via a percent-encoded bracketed IPv6 literal or an IP literal with a trailing dot. A host such as %5B%3A%3Affff%3A127%2E0%2E0%2E1%5D (decoding to [::ffff:127.0.0.1]) or 127.0.0.1. is not an IP address to a caller's allowlist built on uri_string:parse/1 and inet:parse_address/1, while hackney connects to the address it denotes. The same applies to a Location target when redirects are followed. The IP-literal gate that hackney_url:normalize/2 applies to a percent-decoded host, added to close the percent-encoded IP bypass of CVE-2026-47076, passes the decoded value to inet_parse:address/1 as is. The connect path in hackney_happy:parse_address/1 drops a surrounding bracket pair, and the resolver ignores a trailing dot, so both forms pass the gate and still reach the literal address. Domain names with a trailing dot and unencoded IPv6 literals are not affected. This issue affects hackney: from 4.0.1 before 4.9.0.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-115700 since 10/25/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available.

Upgrading to version 4.9.0 eliminates this vulnerability.

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Productinfo

Vendor

• benoitc

Name

• hackney

Version

• 4.8.0
• 4.8.1
• 4.8.2
• 4.8.3
• 4.8.4
• 4.8.5
• 4.8.6
• 4.8.7
• 4.8.8
• 4.8.9
• 4.8.10
• 4.8.11
• 4.8.12
• 4.8.13
• 4.8.14
• 4.8.15
• 4.8.16
• 4.8.17
• 4.8.18
• 4.8.19
• 4.8.20
• 4.8.21
• 4.8.22
• 4.8.23
• 4.8.24
• 4.8.25
• 4.8.26
• 4.8.27
• 4.8.28
• 4.8.29
• 4.8.30
• 4.8.31
• 4.8.32
• 4.8.33
• 4.8.34
• 4.8.35
• 4.8.36
• 4.8.37
• 4.8.38
• 4.8.39
• 4.8.40
• 4.8.41
• 4.8.42
• 4.8.43
• 4.8.44
• 4.8.45
• 4.8.46
• 4.8.47
• 4.8.48
• 4.8.49
• 4.8.50
• 4.8.51
• 4.8.52
• 4.8.53
• 4.8.54
• 4.8.55
• 4.8.56
• 4.8.57
• 4.8.58
• 4.8.59
• 4.8.60
• 4.8.61
• 4.8.62
• 4.8.63
• 4.8.64
• 4.8.65
• 4.8.66
• 4.8.67
• 4.8.68
• 4.8.69
• 4.8.70
• 4.8.71
• 4.8.72
• 4.8.73
• 4.8.74
• 4.8.75
• 4.8.76
• 4.8.77
• 4.8.78
• 4.8.79
• 4.8.80
• 4.8.81
• 4.8.82
• 4.8.83
• 4.8.84
• 4.8.85
• 4.8.86
• 4.8.87
• 4.8.88
• 4.8.89
• 4.8.90
• 4.8.91
• 4.8.92
• 4.8.93
• 4.8.94
• 4.8.95
• 4.8.96
• 4.8.97
• 4.8.98
• 4.8.99

Website

• Product: https://github.com/benoitc/hackney/

CPE 2.3info

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