CVE-2026-54321: Daytona Public Sandbox Previews Remain Accessible Vulnerability

HIGH
Advisory Identifier: GHSA-ww63-pv5x-vfc8
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CVSS 7.0
CWE-613 CWE-863
Published
Advisory Summary

CVE-2026-54321 is a HIGH (CVSS 7.0) public sandbox previews remain accessible vulnerability (CWE-613: Insufficient Session Expiration) affecting Daytona libraries in the Go ecosystem. The issue involves public sandbox previews remain accessible for up to one hour after being made private. Remediation is available by upgrading affected packages to version 0.184.0.

CVE-2026-54321 at a Glance

CVE Identifier CVE-2026-54321
GHSA Identifier GHSA-ww63-pv5x-vfc8
Severity HIGH
CVSS v3.1 Base Score 7.0
CWE Classification CWE-613: Insufficient Session Expiration
Affected Product Daytona
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 7.0

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:L).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2026-54321

To remediate this vulnerability, upgrade all affected Daytona dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/daytonaio/daytona fixed: 0.184.0 
Upgrade github.com/daytonaio/daytona to 0.184.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

inspect dependencies for github.com/daytonaio/daytona

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-54321, inspect your project dependencies for Daytona:

inspect dependencies for github.com/daytonaio/daytona

Analyze the terminal output to locate any version of Daytona in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.184.0), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-613: Insufficient Session Expiration, where according to wasc, "insufficient session expiration is when a web site permits an attacker to reuse old session credentials or session ids for authorization.". In Daytona, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary Sandbox previews that were switched from public to private could remain reachable without authentication for a short period after the change, due to a cached visibility state that was not invalidated when the sandbox's visibility changed. ### Impact When a sandbox owner changed a preview from public to private, the preview proxy could continue serving unauthenticated requests to that sandbox's ordinary preview ports for a bounded period before the change took effect. Only sandboxes that had been made public and were later set back to private were affected, and only until the proxy's cached visibility state was refreshed. Terminal, toolbox, and recording-dashboard ports were never affected, as those always require authentication. The issue did not involve cross-tenant access, privilege escalation, or remote code execution. ### Patches Fixed in v0.184.0. Sandbox visibility changes now invalidate the proxy's cached preview state immediately, so revoking a public preview takes effect on the next request. ### Workarounds Upgrade to v0.184.0 or later. There is no configuration workaround for earlier versions. ### Credit Reported through Daytona's Vulnerability Disclosure Program by **mrknightnidu(nidalkhan)**. **Linkedin**: https://www.linkedin.com/in/mrknight-nidu-031340328/

CVE-2026-54321 Affected Daytona Versions

1 component(s)
Fixed Versions:
0.184.0
Product / Package Ecosystem Affected Versions Fixed Version
github.com/daytonaio/daytona
golang/github.com/daytonaio/daytona
Go
≥ 0.101.0
< 0.184.0
0.184.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/daytonaio/daytona/security/advisories/GHSA-ww63-pv5x-vfc8
NVD — CVE-2026-54321 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-54321
Daytona Source Repository REPOSITORY
https://github.com/daytonaio/daytona

Frequently Asked Questions

What is CVE-2026-54321?
CVE-2026-54321 is a security vulnerability in Daytona involving Public sandbox previews remain accessible for up to one hour after being made private under CWE-613: Insufficient Session Expiration.
Which Daytona versions are affected?
Affected versions include releases prior to 0.184.0 across affected packages: github.com/daytonaio/daytona.
What version fixes CVE-2026-54321?
Upgrading to 0.184.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/daytonaio/daytona affected?
Yes, github.com/daytonaio/daytona is affected in releases prior to 0.184.0. Upgrade your dependency to 0.184.0 or later.
What is the CVSS score of CVE-2026-54321?
CVE-2026-54321 has a CVSS v3.1 base score of 7.0 (HIGH) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:L.
What CWE is associated with CVE-2026-54321?
CVE-2026-54321 is classified under CWE-613: Insufficient Session Expiration (According to WASC, "Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization.").
How can I check Go dependencies for CVE-2026-54321?
Run the dependency tree command: 'inspect dependencies for github.com/daytonaio/daytona'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-ww63-pv5x-vfc8",
  "modified" : "2026-07-20T21:14:49Z",
  "published" : "2026-06-16T21:05:13Z",
  "aliases" : [ "CVE-2026-54321" ],
  "summary" : "Daytona: Public sandbox previews remain accessible for up to one hour after being made private",
  "details" : "### Summary\nSandbox previews that were switched from public to private could remain reachable without authentication for a short period after the change, due to a cached visibility state that was not invalidated when the sandbox's visibility changed.\n\n### Impact\nWhen a sandbox owner changed a preview from public to private, the preview proxy could continue serving unauthenticated requests to that sandbox's ordinary preview ports for a bounded period before the change took effect. Only sandboxes that had been made public and were later set back to private were affected, and only until the proxy's cached visibility state was refreshed. Terminal, toolbox, and recording-dashboard ports were never affected, as those always require authentication. The issue did not involve cross-tenant access, privilege escalation, or remote code execution.\n\n### Patches\nFixed in v0.184.0. Sandbox visibility changes now invalidate the proxy's cached preview state immediately, so revoking a public preview takes effect on the next request.\n\n### Workarounds\nUpgrade to v0.184.0 or later. There is no configuration workaround for earlier versions.\n\n### Credit\nReported through Daytona's Vulnerability Disclosure Program by **mrknightnidu(nidalkhan)**.\n**Linkedin**: https://www.linkedin.com/in/mrknight-nidu-031340328/",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/daytonaio/daytona"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0.101.0"
      }, {
        "fixed" : "0.184.0"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 0.183.0"
    }
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/daytonaio/daytona/security/advisories/GHSA-ww63-pv5x-vfc8"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-54321"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/daytonaio/daytona"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-613", "CWE-863" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-06-16T21:05:13Z",
    "nvd_published_at" : "2026-06-23T19:17:08Z"
  }
}