CVE-2026-26060: Fleet Password Reset Tokens Remain Valid Vulnerability

MODERATE
Advisory Identifier: GHSA-3458-r943-hmx4
CWE-613
Published
Advisory Summary

CVE-2026-26060 is a MODERATE password reset tokens remain valid vulnerability (CWE-613: Insufficient Session Expiration) affecting Fleet libraries in the Go ecosystem. The issue involves password reset tokens remain valid after password change for 24 hours. Remediation is available by upgrading affected packages to version 4.43.5-0.20260113202849-bbc1aef2987d.

CVE-2026-26060 at a Glance

CVE Identifier CVE-2026-26060
GHSA Identifier GHSA-3458-r943-hmx4
Severity MODERATE
CVSS v3.1 Base Score N/A
CWE Classification CWE-613: Insufficient Session Expiration
Affected Product Fleet
Package Ecosystem Go
Published Date
Last Updated

How to Fix CVE-2026-26060

To remediate this vulnerability, upgrade all affected Fleet 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/fleetdm/fleet/v4 fixed: 4.43.5-0.20260113202849-bbc1aef2987d
Upgrade github.com/fleetdm/fleet/v4 to 4.43.5-0.20260113202849-bbc1aef2987d
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/fleetdm/fleet/v4

How to Check if You Are Affected

To determine whether your application is affected by CVE-2026-26060, inspect your project dependencies for Fleet:

inspect dependencies for github.com/fleetdm/fleet/v4

Analyze the terminal output to locate any version of Fleet in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 4.43.5-0.20260113202849-bbc1aef2987d), 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 Fleet, 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 A vulnerability in Fleet’s password management logic could allow previously issued password reset tokens to remain valid after a user changes their password. As a result, a stale password reset token could be reused to reset the account password even after a defensive password change. ### Impact If an attacker had prior access to a valid password reset token, they could reuse that token within its validity window to reset the user’s password after the user has already changed it. This could result in temporary account takeover. Exploitation requires prior compromise of a password reset token and is further constrained by the token’s 24-hour expiration period. The issue does not allow discovery of reset tokens, does not bypass authentication on its own, and does not affect accounts without an existing valid reset token. ### Workarounds Until patched, users who believe a password reset token may have been exposed should wait for the token to expire before reusing the account, or contact a Fleet administrator to invalidate active sessions. ### For more information If there are any questions or comments about this advisory: Email Fleet at [security@fleetdm.com](mailto:security@fleetdm.com) Join #fleet in [osquery Slack](https://join.slack.com/t/osquery/shared_invite/zt-h29zm0gk-s2DBtGUTW4CFel0f0IjTEw) ### Credits Fleet thanks @fuzzztf for responsibly reporting this issue.

CVE-2026-26060 Affected Fleet Versions

1 component(s)
Fixed Versions:
4.43.5-0.20260113202849-bbc1aef2987d
Product / Package Ecosystem Affected Versions Fixed Version
github.com/fleetdm/fleet/v4
Go
< 4.43.5-0.20260113202849-bbc1aef2987d
4.43.5-0.20260113202849-bbc1aef2987d

References

Frequently Asked Questions

What is CVE-2026-26060?
CVE-2026-26060 is a security vulnerability in Fleet involving Password reset tokens remain valid after password change for 24 hours under CWE-613: Insufficient Session Expiration.
Which Fleet versions are affected?
Affected versions include releases prior to 4.43.5-0.20260113202849-bbc1aef2987d across affected packages: github.com/fleetdm/fleet/v4.
What version fixes CVE-2026-26060?
Upgrading to 4.43.5-0.20260113202849-bbc1aef2987d (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/fleetdm/fleet/v4 affected?
Yes, github.com/fleetdm/fleet/v4 is affected in releases prior to 4.43.5-0.20260113202849-bbc1aef2987d. Upgrade your dependency to 4.43.5-0.20260113202849-bbc1aef2987d or later.
What CWE is associated with CVE-2026-26060?
CVE-2026-26060 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-2026-26060?
Run the dependency tree command: 'inspect dependencies for github.com/fleetdm/fleet/v4'. 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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-3458-r943-hmx4",
  "modified" : "2026-03-27T21:47:33Z",
  "published" : "2026-03-27T18:17:09Z",
  "aliases" : [ "CVE-2026-26060" ],
  "summary" : "Fleet: Password reset tokens remain valid after password change for 24 hours",
  "details" : "### Summary\n\nA vulnerability in Fleet’s password management logic could allow previously issued password reset tokens to remain valid after a user changes their password. As a result, a stale password reset token could be reused to reset the account password even after a defensive password change.\n\n### Impact\n\nIf an attacker had prior access to a valid password reset token, they could reuse that token within its validity window to reset the user’s password after the user has already changed it. This could result in temporary account takeover.\n\nExploitation requires prior compromise of a password reset token and is further constrained by the token’s 24-hour expiration period. The issue does not allow discovery of reset tokens, does not bypass authentication on its own, and does not affect accounts without an existing valid reset token.\n\n### Workarounds\n\nUntil patched, users who believe a password reset token may have been exposed should wait for the token to expire before reusing the account, or contact a Fleet administrator to invalidate active sessions.\n\n### For more information\n\nIf there are any questions or comments about this advisory:\n\nEmail Fleet at [security@fleetdm.com](mailto:security@fleetdm.com)  \nJoin #fleet in [osquery Slack](https://join.slack.com/t/osquery/shared_invite/zt-h29zm0gk-s2DBtGUTW4CFel0f0IjTEw)\n\n### Credits\n\nFleet thanks @fuzzztf for responsibly reporting this issue.",
  "severity" : [ {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/fleetdm/fleet/v4"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.43.5-0.20260113202849-bbc1aef2987d"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/fleetdm/fleet/security/advisories/GHSA-3458-r943-hmx4"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-26060"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/fleetdm/fleet"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-613" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-27T18:17:09Z",
    "nvd_published_at" : "2026-03-27T19:16:42Z"
  }
}