CVE-2021-39213Network attack vector

API authorization bypass via spoofed proxy header

Published Sep 15, 2021 · Updated Aug 4, 2024

Improper access control in GLPI 9.1 through 9.5.5 allows remote authenticated users to bypass REST API IP restrictions. The API access-control path trusted a client-supplied HTTP_X_FORWARDED_FOR value as the request source address instead of the server-provided address. The REST API must be enabled, an IP restriction configured, and valid API credentials available; access remains bounded by those credentials.

CVSS severity6.8
Medium
EPSS probability1.05%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in GLPI 9.1 through 9.5.5 allows remote authenticated users to bypass REST API IP restrictions. The API access-control path trusted a client-supplied HTTP_X_FORWARDED_FOR value as the request source address instead of the server-provided address. The REST API must be enabled, an IP restriction configured, and valid API credentials available; access remains bounded by those credentials.

The record

CVE
CVE-2021-39213
Published
Sep 15, 2021
Updated
Aug 4, 2024
Vendor
GLPI Project
Product
GLPI
Classifications
CWE-74, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 9.1, < 9.5.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

GLPI Project · GLPIversion=>= 9.1, < 9.5.6

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.0NIST NVDAV:N/AC:M/Au:S/C:P/I:P/A:P
6.8GitHub, Inc.CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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