Is CVE-2018-12372 being actively exploited?

CVE-2018-12372 is not currently listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

What is the CVSS score for CVE-2018-12372?

CVE-2018-12372 has a CVSS 3.0 base score of 6.5 (MEDIUM).

CVE-2018-12372

MEDIUM · CVSS 6.5EPSS 2.5%EU EUVD

Decrypted S/MIME parts, when included in HTML crafted for an attack, can leak plaintext when included in a a HTML reply/forward. This vulnerability affects Thunderbird < 52.9.

Key facts

CVSS score: 6.5 (v3.0)
Severity: MEDIUM
CVSS vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Weakness (CWE): CWE-200
EPSS score: 2.5% (84th percentile)
In CISA KEV: No
In EU EUVD: Yes (EUVD-2018-4346)
Published: October 18, 2018
NVD last modified: June 17, 2026
Status: Modified

EU Vulnerability Database (EUVD)

This vulnerability is also tracked by ENISA as EUVD-2018-4346 in the EU Vulnerability Database. Last updated in EUVD on August 5, 2024.

View on the EU Vulnerability Database

Affected products

canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
canonical / ubuntu linux
debian / debian linux
debian / debian linux
mozilla / thunderbird
redhat / enterprise linux
redhat / enterprise linux
redhat / enterprise linux
redhat / enterprise linux
redhat / enterprise linux desktop
redhat / enterprise linux desktop
redhat / enterprise linux server
redhat / enterprise linux server
redhat / enterprise linux workstation
redhat / enterprise linux workstation

Certified products that may be affected

8 FIPS 140 or Common Criteria certified products, from automated matching by sec-certs.org.

Red Hat Enterprise Linux 7 NSS Cryptographic Module - Red Hat®, Inc. - FIPS 140 4498 - historical
Red Hat Enterprise Linux 7 Kernel Crypto API Cryptographic Module - Red Hat®, Inc. - FIPS 140 3939 - historical
Red Hat Enterprise Linux 7 OpenSSH Server Cryptographic Module - Red Hat®, Inc. - FIPS 140 3891 - historical
Red Hat Enterprise Linux 7 OpenSSH Client Cryptographic Module - Red Hat®, Inc. - FIPS 140 3892 - historical
Red Hat Enterprise Linux 7 OpenSSL Cryptographic Module - Red Hat®, Inc. - FIPS 140 3867 - historical

See all 8 in the Security Certifications Explorer.

References

http://www.securityfocus.com/bid/104613(Third Party Advisory, VDB Entry)
https://access.redhat.com/errata/RHSA-2018:2251(Third Party Advisory)
https://access.redhat.com/errata/RHSA-2018:2252(Third Party Advisory)
https://bugzilla.mozilla.org/show_bug.cgi?id=1419417(Issue Tracking, Permissions Required, Vendor Advisory)
https://lists.debian.org/debian-lts-announce/2018/07/msg00013.html(Mailing List, Third Party Advisory)
https://security.gentoo.org/glsa/201811-13(Third Party Advisory)
https://usn.ubuntu.com/3714-1/(Third Party Advisory)
https://www.debian.org/security/2018/dsa-4244(Third Party Advisory)
https://www.mozilla.org/security/advisories/mfsa2018-18/(Vendor Advisory)

Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS

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