GitHub Enterprise Server fixes a high-severity vulnerability

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[TLP:CLEAR] GitHub Enterprise Server fixes a high-severity vulnerability

GitHub fixes a high-severity vulnerability in GitHub Enterprise Server in versions 3.21.4, 3.20.6, 3.19.10, 3.18.13 and 3.17.19 [1].

GitHub Enterprise Server - arbitrary file deletion (CVE-2026-17556)

CVSS 8.8 (High)

An unauthenticated remote attacker can carry out a path traversal attack and thereby delete any files and folders on the affected instance [1].

The vulnerability is present in product:

GitHub Enterprise Server; >=3.21.0, <3.21.4; >=3.20.0, <3.20.6; >=3.19.10, <3.19.10; >=3.18.0, <3.18.13; >=3.17.0, <3.17.19;

CVSS: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N

More information:

CVE-2026-17556 at cve.org, NVD
CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') at cwe.mitre.org

The vulnerability was publicly disclosed 5. 8. 2026.

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[TLP:CLEAR] GitHub Enterprise Server fixes a high-severity vulnerability

GitHub Enterprise Server - arbitrary file deletion (CVE-2026-17556)

CVSS 8.8 (High)

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