Is CVE-2026-44883 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-44883 being exploited in the wild.

How severe is CVE-2026-44883?

High severity, with a CVSS score of 7.5, published 28 May 2026.

Which products and versions are affected?

github.com/portainer/portainer (Go) SEMVER:introduced=0, SEMVER:introduced=2.33.0,fixed=2.33.8; Portainer >= 2.33.0, = 2.39.0, = 2.40.0, = 2.33.0, = 2.39.0, = 2.40.0, < 2.41.0.

Is there a fix for CVE-2026-44883?

Yes. github.com/portainer/portainer (Go): upgrade to 2.33.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-44883 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-44883?

Check whether you run github.com/portainer/portainer (Go), Portainer or Portainer Community Edition at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-44883: Portainer Community Edition sensitive token leakage via URL query parameter

Q: Is there a fix for CVE-2026-44883?

Yes. github.com/portainer/portainer (Go): upgrade to 2.33.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-44883 attacked?

It is attacked over the network, in a network appliance.

Q: Am I affected by CVE-2026-44883?

Check whether you run github.com/portainer/portainer (Go), Portainer or Portainer Community Edition at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-44883 · Severity: high · CVSS 7.5 · Published 2026-05-28

Portainer is a management platform for Docker and Kubernetes environments. A security flaw allowed sensitive login tokens to be passed in web addresses (URLs), which are often recorded in server logs, browser history, and shared links. If an attacker obtains one of these leaked tokens, they can take full control of the victim's account, potentially allowing them to manipulate or shut down critical container infrastructure.

Technologies: github.com/portainer/portainer (Go), Portainer, Portainer Community Edition. Vendors: Go, Portainer.

Quick answers

Is CVE-2026-44883 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-44883 being exploited in the wild.
How severe is CVE-2026-44883?: High severity, with a CVSS score of 7.5, published 28 May 2026.
Which products and versions are affected?: github.com/portainer/portainer (Go) SEMVER:introduced=0, SEMVER:introduced=2.33.0,fixed=2.33.8; Portainer >= 2.33.0, < 2.33.8; >= 2.39.0, < 2.39.2; >= 2.40.0, < 2.41.0; Portainer Community Edition >= 2.33.0, < 2.33.8; >= 2.39.0, < 2.39.2; >= 2.40.0, < 2.41.0.
Is there a fix for CVE-2026-44883?: Yes. github.com/portainer/portainer (Go): upgrade to 2.33.8 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-44883 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-44883?: Check whether you run github.com/portainer/portainer (Go), Portainer or Portainer Community Edition at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/portainer/portainer (Go): upgrade to 2.33.8 or later
```
go get github.com/portainer/portainer@v2.33.8
```

Technical details

Portainer's authentication middleware (specifically in `api/http/security/bouncer.go`) was configured to accept JWT bearer tokens via the `?token=` URL query parameter. Because URLs are frequently logged by reverse proxies, stored in browser history, and transmitted in `Referer` headers during outbound navigation, these sensitive tokens could be intercepted by unauthorized parties. An attacker who obtains a leaked JWT can achieve full account takeover for the duration of the token's validity. The vulnerability was particularly prevalent in features using WebSockets, such as container console (exec) and shell attaches. The fix removes query-parameter token acceptance in favor of the `Authorization` header and HttpOnly cookies.

Affected products

Portainer Portainer >= 2.33.0, < 2.33.8; >= 2.39.0, < 2.39.2; >= 2.40.0, < 2.41.0

Identifiers

CVE-2026-44883
GHSA-jvp4-q659-95mj
GO-2026-5480

Timeline

2026-03-06: disclosed: Reported via GitHub Security Advisory by scanpwn
2026-04-14: patched: Fix merged to develop branch
2026-04-29: advisory: Version 2.41.0 released
2026-05-07: advisory: LTS versions 2.39.2 and 2.33.8 released

References

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