CVE-2026-44883Network attack vector

Account takeover via JWT query-string exposure

Published May 28, 2026 · Updated May 28, 2026

Sensitive information exposure in affected Portainer Community Edition releases allows attackers to steal JWT bearer tokens from request URLs. Authentication middleware treats the token query parameter as a bearer credential, causing URLs to preserve the JWT in proxy logs, browser history, and outbound Referer headers. Anyone who obtains a leaked token can act with the issuing user’s full privileges until expiry; browser exec and attach workflows expose non-administrators as well.

CVSS severity7.7
High
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sensitive information exposure in affected Portainer Community Edition releases allows attackers to steal JWT bearer tokens from request URLs. Authentication middleware treats the token query parameter as a bearer credential, causing URLs to preserve the JWT in proxy logs, browser history, and outbound Referer headers. Anyone who obtains a leaked token can act with the issuing user’s full privileges until expiry; browser exec and attach workflows expose non-administrators as well.

The record

CVE
CVE-2026-44883
Published
May 28, 2026
Updated
May 28, 2026
Vendor
Portainer
Product
Portainer Community Edition
Classifications
CWE-598, T1528
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 28, 2026CVE publishedPublication date reported by the CVE source.
  2. May 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>= 2.33.0, < 2.33.8
  2. Affected versionversion=>= 2.39.0, < 2.39.2
  3. Affected versionversion=>= 2.40.0, < 2.41.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Portainer · Portainer Community Editionversion=>= 2.33.0, < 2.33.8; version=>= 2.39.0, < 2.39.2; version=>= 2.40.0, < 2.41.0

Published CVSS scores

7.5NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
7.7GitHubCVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-598Use of HTTP Request With Sensitive Query String
T1528Steal Application Access Token

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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