Evidence used
- No CISA KEV confirmation is currently recorded.
- A structured source references public exploit or proof-of-concept material.
- EPSS is 1.06% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2023
CVE-2023-37908High confidence
org.xwiki.rendering:xwiki-rendering-xml Improper Neutralization of Invalid Characters in Identifiers in Web Pages vulnerability
xwiki · xwiki-rendering
Official source articles: GitHub GHSA-663W-2XP3-5739 ↗ · GitHub GHSA-6GF5-C898-7RXP ↗. Check the applicable product and release in the original source.
9.1CriticalCVSS 3.1
Within 72 hours
Patch availableCritical technical impact and a public exploit reference; no CISA KEV confirmation is currently recorded.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityCritical→Operational priority:Critical, unchanged from published severity.unchanged
Compensating controls
- Validate the affected product branch and deploy the verified fixed release.
- Restrict the affected network interface to trusted sources where business-safe.
- Increase monitoring for the attack path and post-exploitation behaviour described in the report.
Verification
- Confirm that the asset runs xwiki xwiki-rendering and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Critical technical impact and a public exploit reference; no CISA KEV confirmation is currently recorded.
Patch available01
What, why and how
XWiki Rendering is a generic Rendering system that converts textual input in a given syntax into another syntax. The cleaning of attributes during XHTML rendering, introduced in version 14.6-rc-1, allowed the injection of arbitrary HTML code and thus cross-site scripting via invalid attribute names. This can be exploited, e.g., via the link syntax in any content that supports XWiki syntax like comments in XWiki. When a user moves the mouse over a malicious link, the malicious JavaScript code is executed in the context of the user session. When this user is a privileged user who has programming rights, this allows server-side code execution with programming rights, impacting the confidentiality, integrity and availability of the XWiki instance. While this attribute was correctly recognized as not allowed, the attribute was still printed with a prefix `data-xwiki-translated-attribute-` without further cleaning or validation. This problem has been patched in XWiki 14.10.4 and 15.0 RC1 by removing characters not allowed in data attributes and then validating the cleaned attribute again. There are no known workarounds apart from upgrading to a version including the fix.
What
XWiki Rendering is a generic Rendering system that converts textual input in a given syntax into another syntax. The cleaning of attributes during XHTML rendering, introduced in version 14.6-rc-1, allowed the injection of arbitrary HTML code and thus cross-site scripting via invalid attribute names. This can be exploited, e.g., via the link syntax in any content that supports XWiki syntax like comments in XWiki. When a user moves the mouse over a malicious link, the malicious JavaScript code is executed in the context of the user session. When this user is a privileged user who has programming rights, this allows server-side code execution with programming rights, impacting the confidentiality, integrity and availability of the XWiki instance. While this attribute was correctly recognized as not allowed, the attribute was still printed with a prefix `data-xwiki-translated-attribute-` without further cleaning or validation. This problem has been patched in XWiki 14.10.4 and 15.0 RC1 by removing characters not allowed in data attributes and then validating the cleaned attribute again. There are no known workarounds apart from upgrading to a version including the fix.
Why
The product does not neutralize or incorrectly neutralizes javascript: or other URIs from dangerous attributes within tags, such as onmouseover, onload, onerror, or style.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
What
XWiki Rendering is a generic Rendering system that converts textual input in a given syntax into another syntax. The cleaning of attributes during XHTML rendering, introduced in version 14.6-rc-1, allowed the injection of arbitrary HTML code and thus cross-site scripting via invalid attribute names. This can be exploited, e.g., via the link syntax in any content that supports XWiki syntax like comments in XWiki. When a user moves the mouse over a malicious link, the malicious JavaScript code is executed in the context of the user session. When this user is a privileged user who has programming rights, this allows server-side code execution with programming rights, impacting the confidentiality, integrity and availability of the XWiki instance. While this attribute was correctly recognized as not allowed, the attribute was still printed with a prefix `data-xwiki-translated-attribute-` without further cleaning or validation. This problem has been patched in XWiki 14.10.4 and 15.0 RC1 by removing characters not allowed in data attributes and then validating the cleaned attribute again. There are no known workarounds apart from upgrading to a version including the fix.
Why
The product does not neutralize or incorrectly neutralizes javascript: or other URIs from dangerous attributes within tags, such as onmouseover, onload, onerror, or style.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.
02
Exploit reality and attack path
CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.
Observed exploitation No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.
Public PoC / exploit material Reference recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.
- Likely attack path
- a network path → Improper Neutralization of Script in Attributes in a Web Page → cause the confidentiality, integrity or availability impact described by the vendor
- Attack surface
- Network
- Privileges required
- Low: a basic authenticated account is required
- User interaction
- Required interaction required
- Attack complexity
- Low: no specialised conditions are recorded
- Security boundary
- Changed: exploitation can affect a different security authority
- Weakness
?
CWE means Common Weakness Enumeration: a standard category for the underlying weakness. - CWE-83 ↗
CWE-83: Improper Neutralization of Script in Attributes in a Web Page. The product does not neutralize or incorrectly neutralizes javascript: or other URIs from dangerous attributes within tags, such as onmouseover, onload, onerror, or style.
- CVSS vector
?
CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity. CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:HCommon Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.
AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.SChangedScope: The attack can affect a component governed by a different security authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.- Post-exploitation / living off the land
- No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
03
Patch and workaround
Operational remediation based on structured source evidence.
- Status
?
Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change. - Patch available
- Action
- Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
- Workaround
- No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 25 Oct 2023 · Last source change 17 Sept 2024, 13:38 UTC · CWE-83 · Improper Neutralization of Script in Attributes in a Web Page
CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source FIRST · tracked since 2026-08-14
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2023-2666
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.
CVE published
Fixed release or patch reference recorded
Technical terms and abbreviations used in this report
- CVE
- Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
- CVSS
- Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
- EPSS
- Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
- CWE
- Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
- CNA
- CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
- CISA ADP
- Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
- NVD
- National Vulnerability Database: NIST's enrichment service for CVE records.
- CERT / CSIRT
- A computer security incident response team that publishes warnings or coordinates incident response.
- PoC
- Proof of concept: public material that demonstrates or helps reproduce exploitation.
- CSAF
- Common Security Advisory Framework: a machine-readable format for security advisories.
- LoTL
- Living off the land: abuse of legitimate tools or system functions during an attack.