CVE-2021-22867Network attack vector

Authenticated file read via Pages path traversal

Published Jul 14, 2021 · Updated Aug 3, 2024

Path traversal in GitHub Pages builds on GitHub Enterprise Server before 3.1.3 allows remote authenticated users to read instance files. The Pages build pipeline accepts user-controlled configuration options without sufficient path restrictions, allowing configured paths to escape the intended build area. Exploitation requires permission to create and build a GitHub Pages site, and the demonstrated consequence is reading files from the server instance.

CVSS severity6.5
Medium
EPSS probability1.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in GitHub Pages builds on GitHub Enterprise Server before 3.1.3 allows remote authenticated users to read instance files. The Pages build pipeline accepts user-controlled configuration options without sufficient path restrictions, allowing configured paths to escape the intended build area. Exploitation requires permission to create and build a GitHub Pages site, and the demonstrated consequence is reading files from the server instance.

The record

CVE
CVE-2021-22867
Published
Jul 14, 2021
Updated
Aug 3, 2024
Vendor
Twitter
Product
GitHub Enterprise Server
Classifications
CWE-22, CWE-77, T1005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 14, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=2.22 <2.22.17
  2. Affected versionversion=3.0 <3.0.11
  3. Affected versionversion=3.1 <3.1.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Twitter · GitHub Enterprise Serverversion=2.22 <2.22.17; version=3.0 <3.0.11; version=3.1 <3.1.3

Published CVSS scores

6.5NISTCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
4.0NISTAV:N/AC:L/Au:S/C:P/I:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CWE-77Improper Neutralization of Special Elements used in a Command ('Command Injection')
T1005Data from Local System

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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