Path traversal in GitHub Enterprise Server hosted Pages leads to unauthorized file read access

published 2021-11-10 4y ago modified 2026-06-17 4mo ago also EUVD-2021-10005

cvss: 6.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 66%
public exploits: 0; none known

A path traversal vulnerability was identified in GitHub Pages builds on GitHub Enterprise Server that could allow an attacker to read system files. To exploit this vulnerability, an attacker would need permission to create and build a GitHub Pages site on the GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.3 and was fixed in versions 3.0.19, 3.1.11, and 3.2.3. This vulnerability was reported via the GitHub Bug Bounty program.

Patch / fix

fixed in 1

GitHub GitHub Enterprise Server 3.0.19, 3.1.11, 3.2.3

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Exploit prediction

1.13% chance of exploitation in the next 30 days, higher than 66% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD	2.0	4.0	AV:N/AC:L/Au:S/C:P/I:N/A:N

Affected products

GitHub GitHub Enterprise Server

Classification

Weakness

CWE-23 Relative Path Traversal
CWE-22 Improper Limitation of a Pathname to a Restricted Directory

References

Sources

CVE List CVE-2021-22870
NVD CVE-2021-22870

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