CVE-2023-37269 | Winter CMS vulnerable to stored XSS through privileged upload of SVG file

Exp

Winter is a free, open-source content management system (CMS) based on the Laravel PHP framework. Users with the `backend.manage_branding` permission can upload SVGs as the application logo. Prior to version 1.2.3, SVG uploads were not sanitized, which could have allowed a stored cross-site scripting (XSS) attack. To exploit the vulnerability, an attacker would already need to have developer or super user level permissions in Winter CMS. This means they would already have extensive access and control within the system. Additionally, to execute the XSS, the attacker would need to convince the victim to directly visit the URL of the maliciously uploaded SVG, and the application would have to be using local storage where uploaded files are served under the same domain as the application itself instead of a CDN. This is because all SVGs in Winter CMS are rendered through an `img` tag, which prevents any payloads from being executed directly. These two factors significantly limit the potential harm of this vulnerability. This issue has been patched in v1.2.3 through the inclusion of full support for SVG uploads and automatic sanitization of uploaded SVG files. As a workaround, one may apply the patches manually.

Published: 2023-07-07 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-37269 is rated Exploit Available (51.2/100): CVSS Low severity, with medium exploitation likelihood (EPSS 1.32%). Core evidence: 2 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2023-37269

EDB-ID Source Kind Published Link
51591 exploit_db edb 2023-07-15 Exploit-DB ↗
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-37269

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 2026-04-01 1.06% 1.32% +0.26%
2 2026-02-15 1.28% 1.06% -0.23%
3 2026-01-28 1.28%

Full EPSS history (15 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-37269

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
2.0 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
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.
0.5 1.4 [email protected]
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-2023-37269

GitHub Security Advisory for CVE-2023-37269

GHSA-wjw2-4j7j-6gc3 · Severity: low · Ecosystem: composer — Winter CMS stored XSS through privileged upload of SVG file

Affected software / configurations for CVE-2023-37269

Vendor Product Version Raw CPE
wintercms winter < 1.2.3 cpe:2.3:a:wintercms:winter:*:*:*:*:*:*:*:*

References for CVE-2023-37269

cvelogic Threat Intelligence