Portainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. From 2.33.0 to before 2.33.8, 2.39.2, and 2.41.0, Portainer's authentication middleware accepts JWT bearer tokens passed as the ?token=<JWT> URL query parameter on any authenticated API endpoint, in addition to the standard Authorization: Bearer header. URLs are recorded in reverse-proxy access logs, browser history, and HTTP Referer headers on outbound navigation, so any JWT passed this way can be harvested by anyone with access to those logs or by an external site the user subsequently visits. A leaked token grants the full privileges of the user it was issued to, until the token expires (default 8 hours, configurable). The ?token= parameter was used by Portainer's browser-based container attach, exec, and pod shell features, so any user with exec or attach rights on a container was exposed — not only administrators. This vulnerability is fixed in 2.33.8, 2.39.2, and 2.41.0.
History

Thu, 28 May 2026 22:45:00 +0000

Type Values Removed Values Added
First Time appeared Portainer
Portainer portainer
Vendors & Products Portainer
Portainer portainer

Thu, 28 May 2026 21:30:00 +0000

Type Values Removed Values Added
Description Portainer Community Edition is a lightweight service delivery platform for containerized applications that can be used to manage Docker, Swarm, Kubernetes and ACI environments. From 2.33.0 to before 2.33.8, 2.39.2, and 2.41.0, Portainer's authentication middleware accepts JWT bearer tokens passed as the ?token=<JWT> URL query parameter on any authenticated API endpoint, in addition to the standard Authorization: Bearer header. URLs are recorded in reverse-proxy access logs, browser history, and HTTP Referer headers on outbound navigation, so any JWT passed this way can be harvested by anyone with access to those logs or by an external site the user subsequently visits. A leaked token grants the full privileges of the user it was issued to, until the token expires (default 8 hours, configurable). The ?token= parameter was used by Portainer's browser-based container attach, exec, and pod shell features, so any user with exec or attach rights on a container was exposed — not only administrators. This vulnerability is fixed in 2.33.8, 2.39.2, and 2.41.0.
Title Portainer: JWT accepted in URL query leaks tokens to logs and referers
Weaknesses CWE-598
References
Metrics cvssV4_0

{'score': 7.7, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-28T20:59:52.463Z

Reserved: 2026-05-07T21:50:33.544Z

Link: CVE-2026-44883

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-05-28T22:16:59.537

Modified: 2026-05-28T22:16:59.537

Link: CVE-2026-44883

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-28T22:30:27Z