CVE-2026-40110

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Source
https://cve.org/CVERecord?id=CVE-2026-40110
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40110.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-40110
Aliases
Downstream
Related
Published
2026-05-05T21:29:31.323Z
Modified
2026-07-13T07:26:55.845862407Z
Severity
  • 7.6 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:L/SC:L/SI:L/SA:L CVSS Calculator
Summary
jupyter-server CORS origin validation bypass via unanchored regex in allow_origin_pat
Details

Jupyter Server is the backend for Jupyter web applications. In versions 2.17.0 and earlier, the Origin header validation uses Python's re.match() to check incoming origins against the alloworiginpat configuration value. Because re.match() only anchors at the start of the string and does not require a full match, a pattern intended to match only a trusted domain (e.g., trusted.example.com) will also match any origin that begins with that domain followed by additional characters (e.g., trusted.example.com.evil.com). An attacker who controls such a domain can bypass the CORS origin restriction and make cross-origin requests to the Jupyter Server API from an untrusted site. This issue has been fixed in version 2.18.0.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-777"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40110.json"
}
References

Affected packages

Git / github.com/jupyter-server/jupyter_server

Affected ranges

Type
GIT
Repo
https://github.com/jupyter-server/jupyter_server
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
0ceed45a803ca36735f0fcfeb6d9db9430a50aa0
Fixed
057869a327c46730afede3eab0ca2d2e3e74acea
Fixed
49b34392feaa97735b3b777e3baf8f22f2a14ed8
Database specific 
{
    "source": [
        "CPE_RANGE",
        "REFERENCES"
    ],
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "2.18.0"
        }
    ],
    "cpe": "cpe:2.3:a:jupyter:jupyter_server:*:*:*:*:*:*:*:*"
}

Affected versions

0.*
0.0.1
0.0.2
0.0.3
0.0.4
0.0.5
0.1.0
0.1.1
0.2.0
0.3.0
1.*
1.0.0
1.0.0rc1
1.0.0rc10
1.0.0rc11
1.0.0rc12
1.0.0rc13
1.0.0rc14
1.0.0rc15
1.0.0rc16
1.0.0rc2
1.0.0rc3
1.0.0rc4
1.0.0rc5
1.0.0rc6
1.0.0rc7
1.0.0rc8
1.0.0rc9
1.0.1
1.0.2
1.0.3
1.0.4
1.0.5
1.1.0
1.1.1
1.1.2
1.1.3
1.1.4
1.2.0
1.2.1
1.2.2
1.2.3
1.3.0
1.4.0
1.4.1
1.5.0
1.5.1
1.6.0
1.6.1
v1.*
v1.10.0
v1.10.1
v1.10.2
v1.11.0
v1.11.1
v1.11.2
v1.12.0
v1.12.1
v1.13.0
v1.13.1
v1.13.2
v1.13.3
v1.13.4
v1.13.5
v1.15.0
v1.15.1
v1.15.2
v1.15.3
v1.15.4
v1.15.5
v1.15.6
v1.16.0
v1.6.2
v1.6.3
v1.6.4
v1.7.0
v1.7.0a0
v1.7.0a1
v1.7.0a2
v1.8.0
v1.9.0
v2.*
v2.0.0
v2.0.0a0
v2.0.0a1
v2.0.0a2
v2.0.0b0
v2.0.0b1
v2.0.0rc0
v2.0.0rc1
v2.0.0rc2
v2.0.0rc3
v2.0.0rc4
v2.0.0rc5
v2.0.0rc6
v2.0.0rc7
v2.0.0rc8
v2.0.1
v2.0.2
v2.0.3
v2.0.4
v2.0.5
v2.0.6
v2.0.7
v2.1.0
v2.10.0
v2.10.1
v2.11.0
v2.11.1
v2.11.2
v2.12.0
v2.12.1
v2.12.2
v2.12.3
v2.12.4
v2.12.5
v2.13.0
v2.14.0
v2.14.1
v2.14.2
v2.15.0
v2.16.0
v2.17.0
v2.2.0
v2.2.1
v2.3.0
v2.4.0
v2.5.0
v2.6.0
v2.7.0
v2.7.1
v2.7.2
v2.7.3
v2.8.0
v2.9.0
v2.9.1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40110.json"