CVE-2026-55878
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk4th percentile - higher than 4% of all known CVEs
Summary
A vulnerability in Symfony UX allows writing files to arbitrary locations or reading local files outside the recipe directory via a crafted recipe kit. The issue affects the ux:install console command which uses Path::isRelative() accepting paths like ../../../etc.
Risk Assessment
An attacker could exploit this to overwrite critical system files or read sensitive data, potentially leading to server compromise or information disclosure.
Recommendation
Immediately upgrade Symfony UX to version 2.36.1 or 3.2.0 depending on your branch. After updating, verify file integrity and configured recipes.
Other vulnerabilities in Symfony UX
See all- CVE-2026-49215Medium
A vulnerability in Symfony UX allows CSRF attacks on LiveComponent components. The protection mechanism relies on the Accept header, which can be set by an attacker in a cross-origin request without preflight, enabling unauthorized actions on a victim's session.
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A vulnerability in Symfony UX allows an attacker to swap a signed data blob between components or slots, enabling the setting of read-only properties on a target component. Affected versions are from 2.8.0 to 2.36.0 and 3.1.0.
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- CVE-2026-49210Medium
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- CVE-2026-49208Medium
A vulnerability in Symfony UX allows an attacker to manipulate dates by sending relative strings (e.g., now, tomorrow, +10 years) to a LiveProp of type DateTimeInterface without a configured format. This bypasses time-based business logic checks.
- CVE-2026-55877Medium
A vulnerability in Symfony UX allows XSS via the ux_icon() Twig function, which marks output as safe (is_safe=['html']) and embeds SVG source verbatim. Unsanitized local SVG files or Iconify JSON responses can contain malicious scripts, event handlers, or dangerous URL schemes.
Original NVD description (English source)
Symfony UX is a JavaScript ecosystem for Symfony. From 2.32.0 before 2.36.1 and from 3.0.0 before 3.2.0, the ux:install console command installs files from a recipe kit by copying paths listed in a copy-files map, and because Path::isRelative() accepts paths like ../../../etc, a crafted or compromised kit can write attacker-controlled content to arbitrary locations or read local files outside the recipe directory. This issue is fixed in versions 2.36.1 and 3.2.0.