# CVE-2026-120248: Thelia before 3.1.1 Stored XSS via SVG Store Logo and Banner Uploads

Status: published. Published: 2026-11-01. Updated: 2026-11-02.

Thelia before 3.1.1 contains a stored cross-site scripting vulnerability that allows authenticated back-office administrators with store update permission to inject scripts by uploading unsanitized SVG logo_file or banner_file images. Attackers can upload an SVG with an onload payload served from /admin/store-media/logo or the public cache/images/store/ directory to execute scripts against visitors and higher-privileged administrators.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/thelia-templates/default-twig/commit/d79780eafc5b17ac75554c836a1853610d89a090
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/thelia-templates/default-twig/commit/f690a649cbbcee9543647cb7ed5018df68f66658
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/thelia/thelia/commit/2c691e5c3bb8536ca901fcf7d2780301bd111ba9

## Affected products and versions

- Thelia / Thelia (thelia/thelia): ≥ 0; < 3.1.1 (affected, semver). Source: CNA: VulnCheck
- Thelia / Thelia Core (thelia/core): ≥ 0; < 3.1.1 (affected, semver). Source: CNA: VulnCheck
- Thelia / Thelia Back-office Default Twig Template (thelia/backoffice-default-twig-template): ≥ 0; < 1.1.1 (affected, semver). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 4.6 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 4.8 (medium); CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N; source: CNA: VulnCheck

- CVSS 4.0: 4.6 (medium); CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X; source: NVD: disclosure@vulncheck.com

- CVSS 3.1: 4.8 (medium); CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N; source: NVD: disclosure@vulncheck.com

- CISA KEV: No listing in collected sources

- EPSS: 0.24% as of 2026-11-02; percentile 14.97%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-79

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/thelia/thelia/security/advisories/GHSA-gvcv-hvpp-89gx (CNA: VulnCheck; vendor-advisory)

- https://github.com/thelia-templates/default-twig/commit/d79780eafc5b17ac75554c836a1853610d89a090 (CNA: VulnCheck; patch)

- https://github.com/thelia-templates/default-twig/commit/f690a649cbbcee9543647cb7ed5018df68f66658 (CNA: VulnCheck; patch)

- https://github.com/thelia/thelia/commit/2c691e5c3bb8536ca901fcf7d2780301bd111ba9 (CNA: VulnCheck; patch)

- https://github.com/thelia/thelia/releases/tag/3.1.1 (CNA: VulnCheck; release-notes)

- https://github.com/thelia-templates/default-twig/blob/6473c164bd86348f4c7d0ef6f194f1ff3d267902/src/Controller/Configuration/ConfigStoreController.php#L173-L195 (CNA: VulnCheck; technical-description)

- https://www.vulncheck.com/advisories/thelia-before-3.1.1-stored-xss-via-svg-store-logo-and-banner-uploads (CNA: VulnCheck; third-party-advisory)

- https://github.com/thelia-templates/default-twig/blob/6473c164bd86348f4c7d0ef6f194f1ff3d267902/src/Controller/Configuration/ConfigStoreController.php#L173-L195 (disclosure@vulncheck.com)

- https://github.com/thelia-templates/default-twig/commit/d79780eafc5b17ac75554c836a1853610d89a090 (disclosure@vulncheck.com)

- https://github.com/thelia-templates/default-twig/commit/f690a649cbbcee9543647cb7ed5018df68f66658 (disclosure@vulncheck.com)

- https://github.com/thelia/thelia/commit/2c691e5c3bb8536ca901fcf7d2780301bd111ba9 (disclosure@vulncheck.com)

- https://github.com/thelia/thelia/releases/tag/3.1.1 (disclosure@vulncheck.com)

- https://github.com/thelia/thelia/security/advisories/GHSA-gvcv-hvpp-89gx (disclosure@vulncheck.com)

- https://www.vulncheck.com/advisories/thelia-before-3.1.1-stored-xss-via-svg-store-logo-and-banner-uploads (disclosure@vulncheck.com)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-120248; retrieved 2026-11-02; source updated 2026-11-02

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-120248; retrieved 2026-11-02; source updated 2026-11-01

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-120248; retrieved 2026-11-02; source updated Not reported

Revision: 2291e3836faea80b3015d47909706345ec24048454d6aba43487883ee2dbacee

Canonical: https://y2.dev/cve/CVE-2026-120248

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