CVE-2026-63179: Winter: Local File Inclusion through @import directives in LESS compilation of backend customizable stylesheets and theme assets
Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.
Generated by VEDAS. Scores as of 2026-11-01 19:19 UTC. Rebuilt every few hours from cve-scores, CISA KEV and vedas-signatures. How this works and its limits.
What it is
Winter CMS is a content management system built on the Laravel PHP framework. In versions up to and including 1.2.12, authenticated backend users can disclose arbitrary files readable by the PHP process by injecting @import (inline) directives into LESS source that the backend compiles, because the LESS parser was instantiated without a safe import resolver and fell back to the raw attacker-supplied path when no allowed root matched. The flaw is reachable through four entry points that share the same root cause: the Brand Settings custom_css field, the Editor Settings html_custom_styles field, the Mail Brand Settings colour-picker fields whose values are concatenated into LESS source without escaping, and theme .less, .sass, and .scss assets compiled when served. Both absolute paths and .. traversal outside the asset’s own tree were accepted, so an attacker could read any file the web process can access, most significantly the application .env file and the APP_KEY and database credentials it contains. Exploitation requires a backend account holding one of the associated permissions, which are assigned by default to the built-in Developer role. This issue is fixed in version 1.2.13.
Description quoted from the CVE record (assigned by GitHub_M, published 2026-08-26).
Weakness: CWE-22: Improper Limitation of a Pathname to a Restricted Directory (‘Path Traversal’)
How it can be exploited
Exploitable over the network with low attack complexity needing high privileges and no user interaction. Impact: confidentiality high, integrity none, availability none. CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
CISA assessment (SSVC): CISA has no evidence of exploitation. Automatable: no. Technical impact: partial.
Public exploit evidence (Exploit Observer)
Also known as: EUVD-2026-66654, GHSA-58fp-mcx6-7qf9
VEDAS cluster: VEDAS:DEEPDESCENT
Exploit Observer links 3 pieces of public exploit code or detection modules that name this CVE or one of its aliases.
Exploit code and modules (3)
Code that names this CVE. A repository can be a working exploit, a scanner, a fake or malware; read it before running anything.
- Code repository: https://raw.githubusercontent.com/ARPSyndicate/vedas-signatures/main/suricata/2026/CVE-2026-63179.rules
- Code repository: https://raw.githubusercontent.com/ARPSyndicate/vedas-signatures/main/suricata/2026/CVE-2026-63179.rules
- Code repository: https://raw.githubusercontent.com/ARPSyndicate/vedas-signatures/main/suricata/2026/CVE-2026-63179.rules
Vulnerability databases and vendor advisories (5)
Catalogue entries, not exploit evidence.
- Vulnerability database or vendor advisory: https://euvd.enisa.europa.eu/enisa/EUVD-2026-66654
- Vulnerability database or vendor advisory: https://github.com/advisories/GHSA-58fp-mcx6-7qf9
- Vulnerability database or vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-63179
- Vulnerability database or vendor advisory: https://osv.dev/vulnerability/CVE-2026-63179
- Vulnerability database or vendor advisory: https://osv.dev/vulnerability/GHSA-58fp-mcx6-7qf9
3 more references returned by Exploit Observer did not name this CVE or an alias, so they are left out.
VEDAS data as of 2026-11-01T17:12 UTC; fetched 2026-11-02.
Live scores
- EPSS
- 0.005
low predicted chance of attack - VEDAS
- 0.987
strong exploit evidence - On CISA KEV
- Not listed
- Detection rule
- Suricata
Who is affected
| Product | Affected | Not affected |
|---|---|---|
| wintercms winter | version < 1.2.13 | Not stated |
Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.
Exploit Observer also maps it to: packagist winter/wn-backend-module.
How to fix it
No fixed version or vendor advisory is listed in the CVE record yet. Watch the vendor’s security page.
How to detect it
Suricata rules (network detection)
1 rule that alert on traffic matching this exploit: VEDAS CVE-2026-63179 Winter CMS - LESS @import Arbitrary File Read via backend settings. Add them to your Suricata rule set and reload.
Show the rules
alert http $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"VEDAS CVE-2026-63179 Winter CMS - LESS @import Arbitrary File Read via backend settings"; flow:established,to_server; http.method; content:"POST"; http.request_body; content:"@import"; nocase; fast_pattern; pcre:"/@import[^\r\n]{0,80}(\.env|\x2fetc\x2f|\.\.[\x2f\x5c])/i"; classtype:web-application-attack; reference:cve,CVE-2026-63179; reference:url,https://www.exploit.observer/?keyword=CVE-2026-63179&match=exact; reference:url,https://subdomain.center/?engine=ammonites&keyword=wintercms&match=exact; sid:1099412; rev:1;)
CVE-2026-63179.rules on GitHub
References
Other references
- https://github.com/wintercms/winter/security/advisories/GHSA-58fp-mcx6-7qf9 (x_refsource_CONFIRM)
- https://github.com/wintercms/storm/commit/af770331c683e628533a6ec2991285d6e10a4d6c (x_refsource_MISC)
- https://github.com/wintercms/winter/commit/130f0ea43e9228bf0d129b481da1cdfbcc4b4456 (x_refsource_MISC)
- https://github.com/wintercms/winter/releases/tag/v1.2.13 (x_refsource_MISC)
Other databases
Where this comes from
This advisory is generated automatically by VEDAS from: CVE.org record, cve-scores (EPSS and VEDAS), Exploit Observer, vedas-signatures. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.