CVE-2019-11727
A vulnerability exists where it possible to force Network Security Services (NSS) to sign CertificateVerify with PKCS#1 v1.5 signatures when those are the only ones advertised by server in CertificateRequest in TLS 1.3.
Does this matter?
Lower severity and a low EPSS score (1.81%). Track it; it rarely justifies an emergency change on its own.
Description
A vulnerability exists where it possible to force Network Security Services (NSS) to sign CertificateVerify with PKCS#1 v1.5 signatures when those are the only ones advertised by server in CertificateRequest in TLS 1.3. PKCS#1 v1.5 signatures should not be used for TLS 1.3 messages. This vulnerability affects Firefox < 68.
- CVSS 3.0
- 5.3 MEDIUMCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- EPSS
- 1.81% probability · 79th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-295
- Affected
- mozilla/firefox
- Source
- security@mozilla.org
EPSS 1.8% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00009.html
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00010.html
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00011.html
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00017.html
- http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00006.html
- https://access.redhat.com/errata/RHSA-2019:1951
- https://bugzilla.mozilla.org/show_bug.cgi?id=1552208Issue Tracking, Permissions Required, Vendor Advisory
- https://security.gentoo.org/glsa/201908-12
- https://www.mozilla.org/security/advisories/mfsa2019-21/Vendor Advisory
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00009.html
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00010.html
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00011.html
- http://lists.opensuse.org/opensuse-security-announce/2019-10/msg00017.html
- http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00006.html
- https://access.redhat.com/errata/RHSA-2019:1951
- https://bugzilla.mozilla.org/show_bug.cgi?id=1552208Issue Tracking, Permissions Required, Vendor Advisory
- https://security.gentoo.org/glsa/201908-12
- https://www.mozilla.org/security/advisories/mfsa2019-21/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.