high CVSS 7.5 EPSS <0.1%

CVE-2026-33182·PHP vulnerability

Saloon is a PHP library that gives users tools to build API integrations and SDKs. Prior to version 4.0.0, when building the request URL, Saloon combined the connector's base URL with the request endpoint. If the endpoint was a valid absolute URL, the code used that URL as-is and ignored the base URL. The request—and any authentication headers, cookies, or tokens attached by the connector—was then sent to the attacker-controlled host. If the endpoint could be influenced by user input or configuration (e.g. redirect_uri, callback URL), this allowed server-side request forgery (SSRF) and/or credential leakage to a third-party host. The fix in version 4.0.0 is to reject absolute URLs in the endpoint: URLHelper::join() throws InvalidArgumentException when the endpoint is a valid absolute URL, unless explicitly allowed, requiring callers to opt-in to the functionality on a per-connector or per-request basis.

Severity
high
Software
PHP
Fixed in
4.0.0
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at <0.1% — higher than 9% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2026-33182 scores 7.5 on CVSS, so a successful attack would be serious — but at <0.1%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

Until: 4.0.0

Fixed in: 4.0.0

How to fix this CVE

Upgrade PHP and the Saloon library to version 4.0.0 or later to mitigate SSRF and credential leakage risks. This update enforces stricter validation of endpoint URLs, preventing attackers from redirecting requests to attacker-controlled hosts while maintaining authentication context. Review your application code to ensure any dynamic endpoint construction is properly validated before passing to Saloon connectors.

sudo dnf update php

Defensia detects this vulnerability

WAF mitigation (if patching is not yet possible)

Add this rule to your WAF to block exploitation attempts while you schedule the patch. 

Implement strict URL validation rules that block requests to internal IP ranges (127.0.0.1, 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) and enforce hostname allowlisting for API endpoints. Additionally, monitor outbound HTTP requests from your application server to non-whitelisted external hosts.

How to check if you are affected

  1. Check installed PHP version: php -v
  2. Verify Saloon library version in composer.lock or vendor directory: grep -A 2 '"name": "saloonphp/saloon"' composer.lock
  3. Search application logs for unusual outbound requests to external hosts not in your configuration: grep -i 'http' /var/log/php-fpm.log | grep -v 'expected.domain.com'
  4. Confirm patch applied by running php -r "echo (new ReflectionClass('Saloon\\Helpers\\URLHelper'))->getFileName();" and verifying Saloon version >= 4.0.0

FAQ

What is CVE-2026-33182?

This vulnerability in the Saloon PHP library allows attackers to perform server-side request forgery (SSRF) by injecting absolute URLs into the endpoint parameter, causing the application to send requests and sensitive authentication credentials to attacker-controlled hosts instead of the intended API endpoint.

Is CVE-2026-33182 being actively exploited?

No, CVE-2026-33182 is not currently listed in the CISA Known Exploited Vulnerabilities catalog, and no public exploit code is available.

What versions of PHP are affected by CVE-2026-33192?

All versions of the Saloon library prior to 4.0.0 are vulnerable; PHP versions themselves are not directly affected, but applications using vulnerable Saloon versions are at risk.

How do I check if my server is vulnerable to CVE-2026-33182?

Run: grep -A 2 '"name": "saloonphp/saloon"' composer.lock and check if the version is less than 4.0.0; if Saloon is installed and version < 4.0.0, your server is vulnerable.

Does Defensia detect CVE-2026-33182?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If PHP and Saloon are installed on a monitored server, CVE-2026-33182 will appear in your dashboard with remediation steps.

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References

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