CVE-2026-86049

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Source
https://cve.org/CVERecord?id=CVE-2026-86049
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-86049.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-86049
Aliases
Downstream
Published
2026-09-17T20:28:52Z
Modified
2026-09-19T03:47:24Z
Severity
  • 7.1 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H CVSS Calculator
Summary
Jupyter Server: 5xx request logging leaks token-bearing Referer header values
Details

Jupyter Server is the backend for Jupyter web applications. Prior to version 2.21.0, the 5xx request logging path in jupyter_server/log.py copies the Referer header into a JSON header block without applying the token scrubbing used for the request URI. A request that returns HTTP 500 while the Referer contains a token-bearing URL can therefore write that token to server logs in plaintext. An attacker who can read those logs can recover the token and use the affected user's Jupyter Server permissions. This issue is fixed in version 2.21.0.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-532"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86049.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
52513529af7096e622c00911b17627b266294717
Fixed
67aca0c1703b3aa42bbbcb35e05c2b5bf2304c3f
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "2.21.0"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

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
v2.18.0
v2.18.1
v2.18.2
v2.19.0
v2.2.0
v2.2.1
v2.20.0
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-2026-86049.json"