thunderbird: flaw in verification of S/MIME signature resulting in signature spoofing
Published Apr 26, 2019
5.3
MEDIUMCVSS 3.0
EPSS 1.68%
Description
A flaw during verification of certain S/MIME signatures causes emails to be shown in Thunderbird as having a valid digital signature, even if the shown message contents aren't covered by the signature. The flaw allows an attacker to reuse a valid S/MIME signature to craft an email message with arbitrary content. This vulnerability affects Thunderbird < 60.5.1.
Affected products
-
- Version unspecifiedStatusaffectedConstraints<60.5.1
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Mozilla | Thunderbird | n/a |
|
- < 60.5.1
No data.
Red Hat Enterprise Linux 6
thunderbird-0:60.6.1-1.el6_10
Fixed · RHSA-2019:0680
Red Hat Enterprise Linux 7
thunderbird-0:60.6.1-1.el7_6
Fixed · RHSA-2019:0681
Red Hat Enterprise Linux 8
thunderbird-0:60.6.1-1.el8
Fixed · RHSA-2019:1144
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | thunderbird-0:60.6.1-1.el6_10 | Fixed | RHSA-2019:0680 |
| Red Hat Enterprise Linux 7 | thunderbird-0:60.6.1-1.el7_6 | Fixed | RHSA-2019:0681 |
| Red Hat Enterprise Linux 8 | thunderbird-0:60.6.1-1.el8 | Fixed | RHSA-2019:1144 |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
1 other source (Red Hat) ▾
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
AV:N/AC:L/Au:N/C:N/I:P/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 3, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (10 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 3, 2026 | 1.68% (0.01676) | 76.07th | v5 (v2026.06.15) |
| Jun 15, 2026 | 1.68% (0.01676) | 73.78th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.28% (0.00280) | 49.33th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.79% (0.00794) | 82.28th | v3 (v2023.03.01) |
| Apr 19, 2024 | 1.37% (0.01369) | 86.08th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.42% (0.01424) | 84.45th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.54% (0.01537) | 74.52th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.54% (0.01537) | 51.33th | v2 (v2022.01.01) |
| Feb 3, 2022 | 2.07% (0.02069) | 50.36th | v5 (v2026.06.15) |
| Apr 14, 2021 | 2.07% (0.02069) | 0.00th | v1 |
References (13)
- http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00043.html vendor-advisoryx_refsource_SUSE
- http://packetstormsecurity.com/files/152703/Johnny-You-Are-Fired.html x_refsource_MISCThird Party AdvisoryVDB Entry
- http://seclists.org/fulldisclosure/2019/Apr/38 mailing-listx_refsource_FULLDISCMailing ListThird Party Advisory
- http://www.openwall.com/lists/oss-security/2019/04/30/4 mailing-listx_refsource_MLISTMailing ListThird Party Advisory
- https://access.redhat.com/errata/RHSA-2019:1144 vendor-advisoryx_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2018-18509 Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1507218 x_refsource_MISCIssue TrackingPermissions RequiredVendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1677613 Issue Tracking
- https://github.com/RUB-NDS/Johnny-You-Are-Fired x_refsource_MISC
- https://github.com/RUB-NDS/Johnny-You-Are-Fired/blob/master/paper/johnny-fired.pdf x_refsource_MISC
- https://nvd.nist.gov/vuln/detail/CVE-2018-18509
- https://www.cve.org/CVERecord?id=CVE-2018-18509
- https://www.mozilla.org/security/advisories/mfsa2019-06/ x_refsource_MISCVendor Advisory
Change history (0)
No recorded changes yet.