CVE-2026-31823 | Sylius has Authenticated Stored XSS

Sylius is an Open Source eCommerce Framework on Symfony. An authenticated stored cross-site scripting (XSS) vulnerability exists in multiple places across the shop frontend and admin panel due to unsanitized entity names being rendered as raw HTML. Shop breadcrumbs (shared/breadcrumbs.html.twig): The breadcrumbs macro uses the Twig |raw filter on label values. Since taxon names, product names, and ancestor names flow directly into these labels, a malicious taxon name like <img src=x onerror=alert('XSS')> is rendered and executed as JavaScript on the storefront. Admin product taxon picker (ProductTaxonTreeController.js): The rowRenderer method interpolates ${name} directly into a template literal building HTML, allowing script injection through taxon names in the admin panel. Admin autocomplete fields (Tom Select): Dropdown items and options render entity names as raw HTML without escaping, allowing XSS through any autocomplete field displaying entity names. An authenticated administrator can inject arbitrary HTML or JavaScript via entity names (e.g. taxon name) that is persistently rendered for all users. The issue is fixed in versions: 1.9.12, 1.10.16, 1.11.17, 1.12.23, 1.13.15, 1.14.18, 2.0.16, 2.1.12, 2.2.3 and above.

Published: 2026-03-10 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-31823 is rated Low Risk (20.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.14%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-31823

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.03% 0.14% +0.12%
2 2026-03-11 0.03%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-31823

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
1.7 2.7 [email protected]

Weakness enumeration for CVE-2026-31823

GitHub Security Advisory for CVE-2026-31823

GHSA-mx4q-xxc9-pf5q · Severity: medium · Ecosystem: composer — Sylius Vulnerable to Authenticated Stored XSS

Affected software / configurations for CVE-2026-31823

Vendor Product Version Raw CPE
sylius sylius >= 2.0.0, < 2.0.16 cpe:2.3:a:sylius:sylius:*:*:*:*:*:*:*:*
sylius sylius >= 2.1.0, < 2.1.12 cpe:2.3:a:sylius:sylius:*:*:*:*:*:*:*:*
sylius sylius >= 2.2.0, < 2.2.3 cpe:2.3:a:sylius:sylius:*:*:*:*:*:*:*:*

References for CVE-2026-31823

cvelogic Threat Intelligence