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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.3% (30-day exploitation probability)+2
- Technical severity (medium)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented mitigation — github.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Sylius Sylius).
- Apply the documented mitigations until a definitive fix is available.
- Exploitation requires user interaction: tighten email/web filtering and warn affected users.
- Search available logs for exploit probes matching the vulnerability class (cross-site scripting), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 4.8 | CVSS 3.1 | Medium | 1.7 | 2.7 | security-advisories@github.com via NIST National Vulnerability Database |
| 4.8 | CVSS 3.1 | Medium | — | — | GitHub_M via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N (score shown at the top: security-advisories@github.com) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.25%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Monitor CSP violation reports and script payloads in reflected parameters.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · sylius/sylius
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 4.8
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
1 on the record
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-108724 Sylius through 2.3.0 Authorization Bypass via Shop API Product-Review Endpoint 4d
- Medium CVE-2026-53637 Sylius: Cart FormComponent allows modification or deletion of an already-completed order Sep 8, 2026
- Medium CVE-2026-53638 Sylius: Channel-based payment method restriction bypass on shop account orders API endpoint Sep 8, 2026
- Medium CVE-2026-53639 Sylius: IDOR on Shop Payment Request API endpoints Sep 8, 2026
- Medium CVE-2026-31824 Sylius has a Promotion Usage Limit Bypass via Race Condition Mar 10, 2026
- Medium CVE-2026-31825 Sylius has a DQL Injection via API Order Filters Mar 10, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-31823 is "Sylius has Authenticated Stored XSS", rated Medium. It affects Sylius (Sylius); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 4.8 describes technical severity. EPSS 0.25% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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