Cyber Resilience

CVE-2024-42008

XSS in Roundcube Webmail ≤ 1.5.8

XSS
Published
05 August 2024
Modified
13 March 2025
Patch / advisory
View advisory
CVSS Score v3.1 9.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
EPSS Score 0.36 98th percentile
Risk Priority 88 floored blend · peak EPSS

Summary

CVE-2024-42008 is a critical-severity Cross-site Scripting (CWE-79) vulnerability in Roundcube Webmail. Its CVSS base score is 9.3 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Browser Session Hijacking (T1185); ranked in the top 2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

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

CVE-2024-42008 is a reflected cross-site scripting flaw (CWE-79) located in the rcmail_action_mail_get->run() handler of Roundcube webmail. The vulnerability affects all releases through 1.5.7 and the 1.6.x branch through 1.6.7; it is triggered when an email attachment is rendered using a dangerous Content-Type header that causes the browser to execute attacker-supplied script in the Roundcube origin.

An unauthenticated remote attacker can exploit the issue by sending a victim a single malicious message containing a crafted attachment. When the recipient opens the message or preview pane, the injected script runs with the user’s Roundcube session privileges, allowing the attacker to exfiltrate message contents, forward or delete mail, and perform other actions within the compromised mailbox.

Roundcube has published patched releases 1.5.8 and 1.6.8 that correct the unsafe header handling; administrators are advised to upgrade immediately. The accompanying security announcements and GitHub release notes contain the precise commit references and upgrade guidance.

The CVE carries a CVSS 3.1 score of 9.3 and an EPSS value that has reached a peak of 0.5857 (current 0.5095). A SonarSource analysis highlights exposure of government mail systems, underscoring the practical impact of the flaw.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

A Cross-Site Scripting vulnerability in rcmail_action_mail_get->run() in Roundcube through 1.5.7 and 1.6.x through 1.6.7 allows a remote attacker to steal and send emails of a victim via a malicious e-mail attachment served with a dangerous Content-Type header.

CWE(s)
CWE-79

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.
attack.mitre.org →
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.
attack.mitre.org →
T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
attack.mitre.org →
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.
attack.mitre.org →
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.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-43770Same product: Roundcube Webmail
CVE-2023-5631Same product: Roundcube Webmail
CVE-2023-47272Same product: Roundcube Webmail
CVE-2020-35730Same product: Roundcube Webmail
CVE-2020-13965Same product: Roundcube Webmail
CVE-2018-6882Same product class: email / collaboration
CVE-2022-27926Same product class: email / collaboration
CVE-2023-43102Same product class: email / collaboration
CVE-2023-34192Same product class: email / collaboration
CVE-2023-24031Same product class: email / collaboration

Affected Assets

roundcube
webmail
≤ 1.5.8 · 1.6.0 — 1.6.8

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

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

Developer testing and evaluation can discover missing or incorrect input neutralization through targeted web-application tests.

SI-10 Information Input Validation good match

Input validation directly enforces neutralization of untrusted data before it reaches web output generation.

SI-15 Information Output Filtering good match

Output filtering can catch or sanitize unneutralized script content before it is served to users.

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.

A.8.29 Security testing in development and acceptance mostly match
finds

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

A.5.6 Contact with special interest groups partial match
prevents

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

A.5.7 Threat intelligence partial match
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.

A.8.25 Secure development life cycle partial match
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.

A.8.28 Secure coding partial match
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.

A.8.7 Protection against malware none match
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