Flarum is an open source forum software. Flarum is affected by a vulnerability that allows an attacker to conduct a Blind Server-Side Request Forgery (SSRF) attack or disclose any file on the server, even with a basic user account on any Flarum forum. By uploading a file containing a URL and spoofing the MIME type, an attacker can manipulate the application to execute unintended actions. The vulnerability is due to the behavior of the intervention/image package, which attempts to interpret the supplied file contents as a URL, which then fetches its contents. This allows an attacker to exploit the vulnerability to perform SSRF attacks, disclose local file contents, or conduct a blind oracle attack. This has been patched in Flarum version 1.8.0. Users are advised to upgrade. Users unable to upgrade may disable PHP's allow_url_fopen which will prevent the fetching of external files via URLs as a temporary workaround for the SSRF aspect of the vulnerability.
CVE-2023-40033
This high-severity CVE scores 7.1 under NVD CVSS v3. EPSS exploit probability: 0.4%, top 66% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.1
- EG Score
- 7.1(medium)
- EG Risk
- 32(Track)EG Risk 32/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity71% × 45%Exploitation0% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 1%
- EPSS %ILE
- 42%
- KEV
- Not listed
Published
August 16, 2023
Last Modified
November 21, 2024
References (4)
- security-advisories@githubhttps://github.com/flarum/framework/commit/d1059c1cc79fe61f9538f3da55e8f42abbede570
- security-advisories@githubhttps://github.com/flarum/framework/security/advisories/GHSA-67c6-q4j4-hccg
- af854a3a-2127-422b-91ae-364da2661108https://github.com/flarum/framework/commit/d1059c1cc79fe61f9538f3da55e8f42abbede570
- af854a3a-2127-422b-91ae-364da2661108https://github.com/flarum/framework/security/advisories/GHSA-67c6-q4j4-hccg
Related CVEs
Related CVEs are temporarily unavailable — the same-product, same-vendor and same-CWE lists could not be loaded just now. That is not a sign that none exist; please retry shortly.
Frequently asked(5)
What is CVE-2023-40033?
When was CVE-2023-40033 disclosed?
Is CVE-2023-40033 actively exploited?
What is the CVSS score of CVE-2023-40033?
How do I remediate CVE-2023-40033?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2023-40033
Is Your Infrastructure Affected by CVE-2023-40033?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.