CVE-2020-26261 json
user-readable api tokens in systemd units
published 2020-12-09 5 y ago modified 2026-09-10 1 mo ago also GHSA-cg54-gpgr-4rm6 , PYSEC-2020-52 , EUVD-2020-0093
- cvss
- 7.9
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 41%
- public exploits
- 0
- none known
Summary
jupyterhub-systemdspawner enables JupyterHub to spawn single-user notebook servers using systemd. In jupyterhub-systemdspawner before version 0.15 user API tokens issued to single-user servers are specified in the environment of systemd units. These tokens are incorrectly accessible to all users. In particular, the-littlest-jupyterhub is affected, which uses systemdspawner by default. This is patched in jupyterhub-systemdspawner v0.15
Patch / fix
- pypi jupyterhub-systemdspawner 0.15.0
- jupyterhub systemdspawner 0.15
Exploit prediction
0.48% chance of exploitation in the next 30 days, higher than 41% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.9 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N |
| NVD | 3.1 | 7.9 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N |
| NVD | 2.0 | 3.3 | AV:L/AC:M/Au:N/C:P/I:P/A:N |
| GitHub | 3.1 | 7.9 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | jupyterhub-systemdspawner | <0.15.0 |
0.15.0 |
Affected products
- jupyterhub systemdspawner
Classification
- Weakness
-
- CWE-668 Exposure of Resource to Wrong Sphere
References
-
github.com
/jupyterhub/systemdspawner/commit/a4d08fd2ade1cfd0ef2c29dc221e649345f23580
web, patch, third-party-advisory
-
github.com
/jupyterhub/systemdspawner/security/advisories/GHSA-cg54-gpgr-4rm6
web, third-party-advisory, advisory
-
github.com
/jupyterhub/systemdspawner/blob/master/CHANGELOG.md#v015
web, release-notes, third-party-advisory
-
pypi.org
/project/jupyterhub-systemdspawner/
product, third-party-advisory, package
-
nvd.nist.gov
/vuln/detail/CVE-2020-26261
advisory
-
github.com
/jupyterhub/systemdspawner
package
-
github.com
/pypa/advisory-database/tree/main/vulns/jupyterhub-systemdspawner/PYSEC-2020-52.yaml
web
-
pypi.org
/project/jupyterhub-systemdspawner
web
Sources
- CVE List CVE-2020-26261
- GitHub Advisory GHSA-cg54-gpgr-4rm6
- NVD CVE-2020-26261
- OSV PYSEC-2020-52
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.