go-chi up to 5.2.x RealIP Middleware access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.8$0-$5k1.44

Summaryinfo

A vulnerability has been found in go-chi chi up to 5.2.x and classified as critical. This issue affects some unknown processing of the component RealIP Middleware. The manipulation leads to access control. This vulnerability is uniquely identified as CVE-2026-72817. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in go-chi chi up to 5.2.x. It has been rated as critical. This issue affects an unknown part of the component RealIP Middleware. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

go-chi/chi versions 0.9.0 before 5.3.0 contains an IP spoofing vulnerability in the RealIP middleware, which resolves the request source IP (Request.RemoteAddr) using the first IP in the X-Forwarded-For header without validating trusted proxies. A malicious client can prepend a forged IP as the first value of the X-Forwarded-For header to spoof the request source IP, potentially bypassing access controls or falsifying request logs.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-72817 since 08/10/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

Upgrading to version 5.3.0 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.9
VulDB Meta Temp Score: 6.8

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: chi 5.3.0

Timelineinfo

08/10/2026 CVE reserved
08/14/2026 +4 days Advisory disclosed
08/14/2026 +0 days VulDB entry created
08/14/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-72817 (🔒)
GCVE (CVE): GCVE-0-2026-72817
GCVE (VulDB): GCVE-100-389987

Entryinfo

Created: 08/14/2026 13:55
Changes: 08/14/2026 13:55 (76)
Complete: 🔍
Cache ID: 216::103

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