How severe is CVE-2019-10740?

CVE-2019-10740 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2019-10740 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-10740?

CVE-2019-10740 primarily affects Roundcube Webmail. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-10740?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2019-10740 published?

CVE-2019-10740 was published on 2019-04-07 and last updated on 2026-06-17.

CVE-2019-10740

CVE-2019-10740 is a medium-severity vulnerability in Roundcube Webmail with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-319.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.3
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-319
Affected product: Roundcube Webmail
Published: 2019-04-07
Last modified: 2026-06-17

Description

In Roundcube Webmail before 1.3.10, an attacker in possession of S/MIME or PGP encrypted emails can wrap them as sub-parts within a crafted multipart email. The encrypted part(s) can further be hidden using HTML/CSS or ASCII newline characters. This modified multipart email can be re-sent by the attacker to the intended receiver. If the receiver replies to this (benign looking) email, they unknowingly leak the plaintext of the encrypted message part(s) back to the attacker.

Frequently asked questions

What is CVE-2019-10740?: In Roundcube Webmail before 1.3.10, an attacker in possession of S/MIME or PGP encrypted emails can wrap them as sub-parts within a crafted multipart email. The encrypted part(s) can further be hidden using HTML/CSS or ASCII newline characters. This modified multipart email can be re-sent by the attacker to the intended receiver. If the receiver replies to this (benign looking) email, they unknowingly leak the plaintext of the encrypted message part(s) back to the attacker.
How severe is CVE-2019-10740?: CVE-2019-10740 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2019-10740 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-10740?: CVE-2019-10740 primarily affects Roundcube Webmail. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-10740?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-10740 published?: CVE-2019-10740 was published on 2019-04-07 and last updated on 2026-06-17.

References

Affected products (6)

cpe:2.3:a:roundcube:webmail:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*
cpe:2.3:a:opensuse:backports_sle:15.0:sp1:*:*:*:*:*:*
cpe:2.3:a:opensuse:backports_sle:15.0:sp2:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*

More vulnerabilities in Roundcube Webmail

CVE-2008-5619 — Critical (CVSS 10.0): html2text.php in Chuggnutt HTML to Text Converter, as used in PHPMailer before 5.2.10, RoundCube Webmail…
CVE-2025-49113 — Critical (CVSS 9.9): Roundcube Webmail before 1.5.10 and 1.6.x before 1.6.11 allows remote code execution by authenticated users because the…
CVE-2024-37385 — Critical (CVSS 9.8): Roundcube Webmail before 1.5.7 and 1.6.x before 1.6.7 on Windows allows command injection via im_convert_path and…
CVE-2021-44026 — Critical (CVSS 9.8): Roundcube before 1.3.17 and 1.4.x before 1.4.12 is prone to a potential SQL injection via search or search_params.
CVE-2020-12641 — Critical (CVSS 9.8): rcube_image.php in Roundcube Webmail before 1.4.4 allows attackers to execute arbitrary code via shell metacharacters…
CVE-2020-12640 — Critical (CVSS 9.8): Roundcube Webmail before 1.4.4 allows attackers to include local files and execute code via directory traversal in a…

All CVEs affecting Roundcube Webmail →

Other CWE-319 (Cleartext Transmission of Sensitive Information) vulnerabilities

CVE-2025-4378 — Critical (CVSS 10.0): Cleartext Transmission of Sensitive Information, Use of Hard-coded Credentials vulnerability in Ataturk University…
CVE-2025-47419 — Critical (CVSS 10.0): Cleartext Transmission of Sensitive Information vulnerability in Crestron Automate VX allows Sniffing Network…
CVE-2026-48902 — Critical (CVSS 9.8): The password and username reset features created plain http links for https connections if the "Force SSL" flag wasn't…
CVE-2025-34271 — Critical (CVSS 9.8): Nagios Log Server versions prior to 2024R2.0.2 contain a vulnerability in the cluster manager component when…
CVE-2025-32880 — Critical (CVSS 9.8): An issue was discovered on COROS PACE 3 devices through 3.0808.0. It implements a function to connect the watch to a…
CVE-2025-26199 — Critical (CVSS 9.8): CloudClassroom-PHP-Project v1.0 is affected by an insecure credential transmission vulnerability. The application…

Browse all CWE-319 (Cleartext Transmission of Sensitive Information) vulnerabilities →