Medium severity · published Jul 9, 2026
CVE-2026-59831
GitHub CLI `gh codespace jupyter` could allow remote code execution when connecting to a malicious Codespace
4.4
CVSS
0.3%
EPSS
No
On KEV
Description
GitHub CLI (gh) is GitHub’s official command line tool. From 2.10.0 through 2.95.0, connecting to a malicious Codespace with gh codespace jupyter can allow command execution because the command opens a JupyterLab URL supplied by a process inside the Codespace without validating that it is a loopback HTTP or HTTPS address, allowing a crafted vscode:// or vscode-insiders:// URL to be handed to VS Code. This issue is fixed in version 2.96.0.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 26% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CL
cli · cli
>= 2.10.0, < 2.96.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-59831
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-59831
github.com
https://github.com/cli/cli/commit/b300f2ec7ec9dc9addc39b2ad88c54097ded7ca0
github.com
https://github.com/cli/cli/releases/tag/v2.96.0
github.com
https://github.com/cli/cli/security/advisories/GHSA-8cg3-r6g9-fpg2
More from cli
9.6
CVE-2024-52308
Connecting to a malicious Codespaces via GH CLI could allow command execution on the user's computer
9.1
CVE-2026-48501
GitHub CLI tokens leak via `gh attestation` commands
6.5
CVE-2024-53858
Recursive repository cloning can leak authentication tokens to non-GitHub submodule hosts in the gh cli
6.3
CVE-2025-25204
`gh attestation verify` returns incorrect exit code during verification if no attestations are present
6.3
CVE-2024-54132
GitHub CLI allows downloading malicious GitHub Actions workflow artifact to result in path traversal vulnerability