CVE-2024-42009: RoundCube Webmail Cross-Site Scripting Vulnerability
Vulnerability summary
CVE-2024-42009 is a critical (CVSS 9.3) Cross-site Scripting vulnerability in Roundcube Webmail. It is known to be exploited: CISA and ENISA list it, first on 09-06-2025. EPSS estimates a 82.88% chance of exploitation in the next 30 days, higher than 99.6% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 5 · Related 2Timeline
- 05-08-2024PublishedVulnerability first disclosed.
- 09-06-2025Added to CISA KEVRoundCube Webmail Cross-Site Scripting Vulnerability
- 30-06-2025CISA remediation dueApply mitigations per vendor instructions.
- 21-10-2025Last modifiedVulnerability information updated.
- 27-04-2026Added to ENISA KEVAdded to the ENISA known exploited vulnerabilities catalog.
Description
A Cross-Site Scripting vulnerability 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 crafted e-mail message that abuses a Desanitization issue in message_body() in program/actions/mail/show.php.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated9.3CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
- OSV · DebianEcosystem advisory · calculated9.3CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
- NVDNIST9.3CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
EPSS trend
Probability
82.88%
Chance of exploitation in the next 30 days
Percentile
100%
Versus all other CVEs
30-day change
0.00 pp
From 82.88% on 20-09-2026
Known exploited
Compare KEV catalogs
CISA KEVListed- Added
- 09-06-2025
- Federal due date
- 30-06-2025
ENISA CNWListed- Added
- 27-04-2026
CISA required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. roundcube.net/news/2024/08/04/security-updates-1.6.8-and-1.5.8 nvd.nist.gov/vuln/detail/CVE-2024-42009
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Debian1 product
- roundcube< 1.6.5+dfsg-1+deb12u3 | < 1.6.8+dfsg-1
Roundcube1 product
- webmail< 1.5.8 | ≥ 1.6.0, < 1.6.8
Ubuntu1 product
- roundcube< 1.6.6+dfsg-2ubuntu0.1+esm1
3 vendors · 3 products
References
12 links- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-42009Government ResourceUS Government Resource
