Skip to content
Fencer Vulns
high 7.5

CVE-2019-11755 json

A crafted S/MIME message consisting of an inner encryption layer and an outer SignedData layer was shown as having a valid digital signatur…

published 2019-09-27 7 y ago modified 2026-06-17 4 mo ago also EUVD-2019-3425

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.3%
EPSS 1.3% chance of exploitation in 30 days, percentile 70%
public exploits
0
none known

Summary

A crafted S/MIME message consisting of an inner encryption layer and an outer SignedData layer was shown as having a valid digital signature, although the signer might have had no access to the contents of the encrypted message, and might have stripped a different signature from the encrypted message. Previous versions had only suppressed showing a digital signature for messages with an outer multipart/signed layer. This vulnerability affects Thunderbird < 68.1.1.

Patch / fix

  • Mozilla Thunderbird 68.1.1
  • thunderbird Debian 14, Debian 13, Debian 12 1:68.2.1-1

debian advisories DEBIAN-CVE-2019-11755

  • thunderbird Ubuntu 16.04 LTS 1:68.7.0+build1-0ubuntu0.16.04.2
  • thunderbird Ubuntu 18.04 LTS 1:68.2.1+build1-0ubuntu0.18.04.1

ubuntu advisories UBUNTU-CVE-2019-11755

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • MozillaThunderbird SLE Workstation Extension 15 SP1, SLE Workstation Extension 15 68.1.1-3.51.1

suse advisories SUSE-SU-2019:2515-1

  • MozillaThunderbird openSUSE Tumbleweed 91.1.1-1.1
  • MozillaThunderbird openSUSE Leap 15.1 68.1.1-lp151.2.13.1
  • enigmail openSUSE Leap 15.1 2.1.2-lp151.2.6.1
  • MozillaThunderbird openSUSE Leap 15.0 68.1.1-lp150.3.51.1
  • enigmail openSUSE Leap 15.0 2.1.2-lp150.34.1

opensuse advisories openSUSE-SU-2024:10601-1openSUSE-SU-2019:2249-1openSUSE-SU-2019:2248-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2019-11755 updated cvss 7.5

thunderbird: spoofing a message author via a crafted S/MIME

  • Red Hat Enterprise Linux 5 thunderbird
    affected: no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 6 thunderbird Red Hat Enterprise Linux 7 thunderbird Red Hat Enterprise Linux 8 thunderbird
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.29% chance of exploitation in the next 30 days, higher than 70% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:P/A:N

Affected products

  • Mozilla Thunderbird

Classification

Weakness
  • CWE-347 Improper Verification of Cryptographic Signature

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.