Vulnerability Database

352,427

Total vulnerabilities in the database

plone.restapi vulnerable to Stored Cross Site Scripting with SVG image in user portrait — plone.restapi

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Impact

There is a stored cross site scripting vulnerability for SVG images uploaded in user portraits.

Note that a page that uses an image tag with an SVG image as source is never vulnerable, even when the SVG image contains malicious code. To exploit the vulnerability, an attacker would first need to upload an SVG image as user portrait, and then trick a user into following a link to this portrait.

Patches

A patch will be released in plone.restapi 8.43.3. This version is good for Plone 6.0, and for Plone 5.2 on Python 3.

In plone.restapi 7 or earlier there was no @portrait endpoint yet, so there is nothing to fix in that version. It is still vulnerable to this attack, and needs a fix in Zope 4. These two vulnerabilities share the same CVE: CVE-2023-42458.

Workarounds

You could remove the portrait field from the member data schema, and possibly remove all portraits that are already in the database, but this seems a bit drastic.

  • Published: Sep 21, 2023
  • Updated: Sep 22, 2023
  • GHSA: GHSA-hc5c-r8m5-2gfh
  • Severity: Low
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Low
  • Score: 3.7
  • AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.