CVE-2023-26478 is a medium-severity (CVSS 6.6) CWE-749 vulnerability in org.xwiki.platform:xwiki-platform-store-filesystem-oldcore. 1 public exploit reference exists, so weaponization risk is real. A fix is available for org.xwiki.platform:xwiki-platform-store-filesystem-oldcore — see the affected versions and patch details below.
org.xwiki.platform:xwiki-platform-store-filesystem-oldcore has Exposed Dangerous Method or Function
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-2023-26478.
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-2023-26478 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 377,636 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
org.xwiki.platform:xwiki-platform-store-filesystem-oldcore☕org.xwiki.platform:xwiki-platform-store-filesystem-oldcoreReal-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
org.xwiki.store.script.TemporaryAttachmentsScriptService#uploadTemporaryAttachment is returning an instance of com.xpn.xwiki.doc.XWikiAttachment. This class is not supported to be exposed to users without the programing right.
com.xpn.xwiki.api.Attachment should be used instead and takes case of checking the user's rights before performing dangerous operations.
Patches
This has been patched in the version 14.9-rc-1 and 14.4.6.
Workarounds
There's no workaround for this issue.
References
https://jira.xwiki.org/browse/XWIKI-20180
For more information
If you have any questions or comments about this advisory:
- Open an issue in JIRA
- Email us at security ML
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.xwiki.platform:xwiki-platform-store-filesystem-oldcore | ≥ 14.3-rc-1&&< 14.4.6 | 14.4.6org.xwiki.platform:xwiki-platform-store-filesystem-oldcore:14.4.6 |
| ☕Maven | org.xwiki.platform:xwiki-platform-store-filesystem-oldcore | ≥ 14.5&&< 14.9-rc-1 | 14.9-rc-1org.xwiki.platform:xwiki-platform-store-filesystem-oldcore:14.9-rc-1 |
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 org.xwiki.platform:xwiki-platform-store-filesystem-oldcore, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.xwiki.platform:xwiki-platform-store-filesystem-oldcore to 14.4.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-26478 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-2023-26478 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-26478. 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-2023-26478 in your dependencies?
O3 Security finds CVE-2023-26478 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.