How severe is CVE-2023-35157?

CVE-2023-35157 has a CVSS score of 8.4/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2023-35157?

CVE-2023-35157 affects the following packages: org.xwiki.platform:xwiki-platform-oldcore (Maven), org.xwiki.platform:xwiki-platform-oldcore (Maven). Ecosystems affected: Maven.

How do I fix CVE-2023-35157?

Update org.xwiki.platform:xwiki-platform-oldcore to 14.10.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-35157 is resolved across your whole dependency graph.

How do I detect CVE-2023-35157 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.xwiki.platform:xwiki-platform-oldcore, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2023-35157 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2023-35157 actively exploited in the wild?

No public exploit code has been indexed for CVE-2023-35157 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2023-35157?

CVE-2023-35157 has an EPSS (Exploit Prediction Scoring System) score of 0.6%, placing it in the 51th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2023-35157?

CVE-2023-35157 is classified as Cross-site Scripting (XSS) (CWE-79), CWE-80 (CWE-80). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2023-35157 published, and has it been updated?

CVE-2023-35157 was published on June 23, 2023 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

HIGH severity

CVE-2023-35157 — xwiki-platform-oldcore

HIGHFix: xwiki/xwiki-platform@35e9073

CVE-2023-35157 is a high-severity (CVSS 8.4) Cross-site Scripting (XSS) vulnerability in org.xwiki.platform:xwiki-platform-oldcore. A fix is available for org.xwiki.platform:xwiki-platform-oldcore — see the affected versions and patch details below.

XWiki Platform vulnerable to reflected cross-site scripting via delattachment action

Also known asGHSA-phwm-87rg-27qq

Published

Jun 23, 2023

Updated

Oct 28, 2026

Affected

2 pkgs

Patched

2 / 2

Exploits

None indexed

Exploitation data as of Nov 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA’s SSVC triage for CVE-2023-35157.

EPSS Exploitation Probability

via FIRST.org ↗

0.6%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs51th percentile — riskier than 51% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

2 pkgs affected

☕org.xwiki.platform:xwiki-platform-oldcore☕org.xwiki.platform:xwiki-platform-oldcore

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Impact

It's possible to perform an XSS by forging a request to a delete attachment action with a specific attachment name. Now this XSS can be exploited only if the attacker knows the CSRF token of the user, or if the user ignores the warning about the missing CSRF token.

Patches

The vulnerability has been patched in XWiki 15.1-rc-1 and XWiki 14.10.6.

Workarounds

There's no workaround for this other than upgrading XWiki.

References

Jira ticket: https://jira.xwiki.org/browse/XWIKI-20339
Commit containing the fix: https://github.com/xwiki/xwiki-platform/commit/35e9073ffec567861e0abeea072bd97921a3decf

For more information

If you have any questions or comments about this advisory:

Open an issue in Jira XWiki.org
Email us at Security Mailing List

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.xwiki.platform:xwiki-platform-oldcore`	≥ 3.2-milestone-3&&< 14.10.6	14.10.6`org.xwiki.platform:xwiki-platform-oldcore:14.10.6`
☕Maven	`org.xwiki.platform:xwiki-platform-oldcore`	≥ 15.0-rc-0&&< 15.1-rc-1	15.1-rc-1`org.xwiki.platform:xwiki-platform-oldcore:15.1-rc-1`

Affected Products

1 product · 2 configurations

Application

xwikixwiki

< 14.10.6

1 version

15.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.xwiki.platform:xwiki-platform-oldcore, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.xwiki.platform:xwiki-platform-oldcore to 14.10.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-35157 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

### Impact It's possible to perform an XSS by forging a request to a delete attachment action with a specific attachment name. Now this XSS can be exploited only if the attacker knows the CSRF token of the user, or if the user ignores the warning about the missing CSRF token. ### Patches The vulnerability has been patched in XWiki 15.1-rc-1 and XWiki 14.10.6. ### Workarounds There's no workaround for this other than upgrading XWiki. ### References * Jira ticket: https://jira.xwiki.org/browse/XWIKI-20339 * Commit containing the fix: https://github.com/xwiki/xwiki-platform/commit/3