CWE-640Weakness · CWE-640

CVE-2026-18363

CRITICAL · 9.1 CVSS v4.0 Published 2026-07-30
No fix yet
No fix has been published. The vendor has not shipped a fixed release or patch. You remain exposed.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click 3 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A logic vulnerability in the password reset token validation routine implemented by osTicket in versions prior to v1.17.8 and v1.18.4. During the password reset process, the application retrieves the timestamp associated with the provided token and checks whether the configured validity period has expired. Consequently, the expiry check is only performed if the timestamp lookup fails, allowing tokens with an existing timestamp to bypass the intended expiry validation. Therefore, an attacker able to obtain a valid password reset token could reuse it to perform an unauthorised password reset and compromise the affected account.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
Authentication
X
User interaction
None
Scope
X

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Recommended fix High confidence

osTicket v1.18.4 (or v1.17.8 as alternative)

  1. 1. Back up your current osTicket installation and database before making any changes
  2. 2. Download osTicket v1.18.4 (the latest stable fixed release) from the official GitHub repository or your preferred distribution channel
  3. 3. Extract the new version files to your web server
  4. 4. Copy your existing configuration file (include/ost-config.php) to the new installation
  5. 5. Ensure any custom plugins, themes, or modifications are compatible with v1.18.4
  6. 6. Run the upgrade script by accessing your osTicket URL - the system should automatically detect the upgrade
  7. 7. Verify the password reset functionality works correctly by testing with a new password reset request
  8. 8. Confirm all users can log in with their existing credentials after upgrade
Caveat Review plugin/theme compatibility before upgrading - custom modifications may require updates

Generated from the published advisory — verify against the referenced sources before acting.

No vendor fix exists The vendor has not published a patch for this.

There is no version to upgrade to and no patch to apply. Every affected install stays exposed until the vendor ships a fix — or somebody else builds one.

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Free · runs locally
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-18363 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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