CVE-2026-125340: Winter cross-site scripting (XSS)

Summary

Winter CMS is a content management system built on the Laravel PHP framework. From 1.0.420 until 1.2.14, the backend Table widget partial modules/backend/widgets/table/partials/_table.php emits the search query parameter without HTML encoding inside a script template. A script-closing sequence in a crafted top-level GET URL terminates the raw-text template and causes the remaining input to be parsed as backend markup, even when the widget uses searching: false. Any Table or DataTable page is a sink, including the core Editor Settings route /backend/system/settings/update/winter/backend/editor, and an unauthenticated attacker can induce an authorized backend user to follow the link. Script executing in the victim's backend origin can read the CSRF token and issue credentialed requests with that user's permissions. For the core sink, a victim with backend.manage_editor, normally a Developer-role user or superuser, can edit CMS templates, so the injected script can conditionally chain to server-side code execution; this does not grant permissions the victim lacks and does not apply automatically to every third-party plugin sink. This issue is fixed in version 1.2.14.

cve.now Index

18Pcve.now Index 18 of 100 · methodology v3 · provisional

Exploitation?/40Unknown. No CISA SSVC exploitation rating yet
Exposure3/25Reachable over the network · Unknown: No advisory context yet
Reach10/20Affects Packagist packages
Severity4.5/10CVSS 4.5
No patch0/5No signal

What would change the score

Would score about 73 if added to CISA KEV
Would score about 68 if CISA's SSVC rates exploitation active
Would score about 37 if advisories confirm default setups are exposed

How the score works · Rankings

What to do

Upgrade to a fixed version: 1.2.14.

Check your systems with an agent

Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.

Check whether my systems are affected by CVE-2026-125340 (Winter CMS: Reflected XSS through the search query parameter in the backend Table widget), using the cve.now data below.

Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only.

What cve.now has for CVE-2026-125340 (entry last updated 2026-11-10):
Affected:
- wintercms winter: from 1.0.420, fixed in 1.2.14
- Packagist package winter/wn-backend-module: from 1.0.420, fixed in 1.2.14
Fixed versions: 1.2.14.
Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory.
CISA KEV: CVE-2026-125340 is not listed as of cve.now's last read.
This KEV status is for CVE-2026-125340 only. If you also check another CVE, look up its own KEV status; never assume it from this one.

How to check:
- Packages (Packagist): find every lockfile in each project and run check_stack from the cve.now MCP server on each one. Compare the resolved versions, not the ranges a manifest declares, with the affected versions above. Include transitive dependencies.
- Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory.

Verify against the linked advisories before concluding, and cite the date you read each one:
- https://github.com/wintercms/winter/security/advisories/GHSA-hq84-x37p-j6q5
- https://github.com/wintercms/winter/commit/1b6397654124fb44a6abf6f3782b6a1d746cef14
- https://github.com/wintercms/winter/releases/tag/v1.2.14
Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing.

Entry: https://cve.now/CVE-2026-125340
For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example get_vulnerability with id CVE-2026-125340.

Timeline

Nov 10, 2026, 8:07 PM UTCCVE published
Nov 10, 2026, 9:10 PM UTCFirst seen by cve.now

Affected versions

wintercms winter
From 1.0.420 · fixed in 1.2.14
winter/wn-backend-modulePackagist
From 1.0.420 · fixed in 1.2.14

Evidence 5

Vendor advisory · 1

Establishes: Affected and fixed versions.

Advisory
GitHub · wintercms/winter · Advisory GHSA-hq84-x37p-j6q5

CVE record · 2

Establishes: The identifier and description.

Record
CVE List · CVE-2026-125340
Record
NVD · CVE-2026-125340

Corrections

None so far.

Something wrong on this page? Report an error. Every fix is listed here.

Questions about CVE-2026-125340

Is CVE-2026-125340 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data

Which versions are affected by CVE-2026-125340?

winter: from 1.0.420 before 1.2.14. winter/wn-backend-module (Packagist): from 1.0.420 before 1.2.14.Source: cve.now feed data

How do I fix CVE-2026-125340?

Upgrade to a fixed version: 1.2.14.Source: cve.now feed data

Winter CMS: Reflected XSS through the search query parameter in the backend Table widget