CVE-2023-42458 is a low-severity (CVSS 3.7) Cross-site Scripting (XSS) vulnerability in zope. 1 public exploit reference exists, so weaponization risk is real. A fix is available for zope — see the affected versions and patch details below.
Zope vulnerable to Stored Cross Site Scripting with SVG images
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-42458.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-42458 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
zope🐍zopeReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Zope is an open-source web application server. Prior to versions 4.8.10 and 5.8.5, there is a stored cross site scripting vulnerability for SVG images. Note that 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 image, and then trick a user into following a specially crafted link. Patches are available in Zope 4.8.10 and 5.8.5. As a workaround, make sure the "Add Documents, Images, and Files" permission is only assigned to trusted roles. By default, only the Manager has this permission.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | zope | all versions | 4.8.10pip install --upgrade 'zope==4.8.10' |
| 🐍PyPI | zope | ≥ 5.8.0&&< 5.8.5 | 5.8.5pip install --upgrade 'zope==5.8.5' |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for zope, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update zope to 4.8.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-42458 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-42458 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-42458. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-42458 in your dependencies?
O3 Security finds CVE-2023-42458 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.