---
title: "CVE-2018-15133: Laravel Deserialization of Untrusted Data Vulnerability"
url: https://erroneo.us/security/cve/CVE-2018-15133/
description: "CVE-2018-15133 (Laravel Laravel Framework): Exploited in the wild (CISA KEV). In Laravel Framework through 5.5.40 and 5.6.x through 5.6.29, remote code…"
type: vulnerability-record
section: "Security Digest"
date_published: 2018-08-09
date_modified: 2025-10-21
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2018-15133"
kev: true
cvss: 8.1
epss: 0.7657
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2018-15133: Laravel Deserialization of Untrusted Data Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Laravel Laravel Framework. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2024-01-16, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2024-02-06 ; treat that as the outer limit, not the target.
- EPSS 76.6% , percentile 99.5: FIRST’s model estimates a 76.6% chance of exploitation activity in the next 30 days, higher than 99.5% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.

## What it is

In Laravel Framework through 5.5.40 and 5.6.x through 5.6.29, remote code execution might occur as a result of an unserialize call on a potentially untrusted X-XSRF-TOKEN value. This involves the decrypt method in Illuminate/Encryption/Encrypter.php and PendingBroadcast in gadgetchains/Laravel/RCE/3/chain.php in phpggc. The attacker must know the application key, which normally would never occur, but could happen if the attacker previously had privileged access or successfully accomplished a previous attack.

## Affected products (CVE record)

- n/a n/a: see advisory

## Severity

- CISA-ADP CVSS 3.1: 8.1 `CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: added 2024-01-16; federal due date 2024-02-06. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 76.57% probability of exploitation activity in the next 30 days; percentile 99.5.

## Sources

- [Listed in CISA KEV notes (laravel.com)](https://laravel.com/docs/5.6/upgrade#upgrade-5.6.30)
- [CVE.org record CVE-2018-15133](https://www.cve.org/CVERecord?id=CVE-2018-15133)
- [NVD entry CVE-2018-15133](https://nvd.nist.gov/vuln/detail/CVE-2018-15133)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-15133)
- [packetstormsecurity.com](http://packetstormsecurity.com/files/153641/PHP-Laravel-Framework-Token-Unserialize-Remote-Command-Execution.html)

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Source page: https://erroneo.us/security/cve/CVE-2018-15133/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt