Cyber Resilience

CVE-2023-29489

XSS in Cpanel ≤ 11.102.0.31

Public PoCHigh EPSSXSS
Published
27 April 2023
Modified
21 November 2024
Patch / advisory
CVSS Score v3.1 5.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
EPSS Score 0.66 99.2th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2023-29489 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Cpanel Cpanel. Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Browser Session Hijacking (T1185); ranked in the top 0.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

An XSS vulnerability, tracked as CVE-2023-29489 and classified under CWE-79, affects the cpsrvd error page in cPanel versions prior to 11.109.9999.116. The flaw is triggered when an invalid webcall ID is supplied, allowing script execution in the context of the error page. It carries a CVSS 3.1 score of 5.3 with local attack vector and low privileges required.

A local attacker with low-privileged access to a cPanel instance can supply a crafted invalid webcall ID to the cpsrvd service and achieve cross-site scripting, potentially leading to theft of session tokens or other client-side actions within the cPanel interface. The issue impacts a large number of cPanel-managed websites according to public analyses.

cPanel's TSR-2023-0001 advisory and associated forums post list the fixed versions as 11.109.9999.116, 11.108.0.13, 11.106.0.18, and 11.102.0.31. Administrators are advised to apply one of these updates to eliminate the XSS vector on the error page. The EPSS score has remained at its peak of 0.9293 without an observable rise after disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

An issue was discovered in cPanel before 11.109.9999.116. XSS can occur on the cpsrvd error page via an invalid webcall ID, aka SEC-669. The fixed versions are 11.109.9999.116, 11.108.0.13, 11.106.0.18, and 11.102.0.31.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1185 Browser Session Hijacking Collection
Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
T1189 Drive-by Compromise Initial Access
Adversaries may gain access to a system through a user visiting a website over the normal course of browsing.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-25837Shared CWE-79
CVE-2023-22438Shared CWE-79
CVE-2023-27614Shared CWE-79
CVE-2023-47164Shared CWE-79
CVE-2023-49145Shared CWE-79
CVE-2023-47853Shared CWE-79
CVE-2023-28474Shared CWE-79
CVE-2023-37636Shared CWE-79
CVE-2023-1006Shared CWE-79
CVE-2023-5005Shared CWE-79

Affected Assets

cpanel
cpanel
≤ 11.102.0.31 · 11.104.0 — 11.106.0.18 · 11.108.0 — 11.108.0.13

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.1.2
  • V1.3.2

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly target introduction of XSS via coding standards/testing (mostly), yet the single broad outcome leaves many specific neutralization vectors unaddressed (partial).

PR.PS-02 partial match
prevents

Patching and EOL replacement can remediate known XSS instances in libraries or frameworks (partial) but do nothing to enforce input neutralization in application code (none).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Secure-coding testing and automated code-analysis tools are applied to detect improper neutralization of script-related content during web-page generation.

prevents

Knowledge exchange on emerging attack techniques and patches reduces the likelihood that cross-site scripting flaws remain unaddressed in deployed applications.

prevents

Operational indicators of compromise for web-application attacks can be incorporated into WAF or input-filtering rules, lowering the likelihood that unsanitized data reaches the browser.

prevents

Requiring language-specific secure-coding standards and automated scanning during the SDLC catches missing output encoding or improper neutralization of untrusted data before the software reaches production.

prevents

Secure-coding standards, SAST scans and removal of insecure code samples together eliminate the failure to neutralize script content that produces cross-site scripting flaws.

none

Webpage malware scanning and block-listing of known malicious sites reduce the likelihood that reflected or stored script payloads reach a user’s browser.

References