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CVE-2021-23991

Published: Jun 24, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUNVD-CWE-Other
NVD MITRE
6.8CVSSMEDIUM
EPSS Score
1.0%
Top 40.6%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

If a Thunderbird user has previously imported Alice's OpenPGP key, and Alice has extended the validity period of her key, but Alice's updated key has not yet been imported, an attacker may send an email containing a crafted version of Alice's key with an invalid subkey, Thunderbird might subsequently attempt to use the invalid subkey, and will fail to send encrypted email to Alice. This vulnerability affects Thunderbird < 78.9.1.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:RS:UC:HI:HA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:HIntegrity
High
A:NAvailability
None
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Weaknesses

NVD-CWE-Other

Affected Products

ThunderbirdMozilla
On-premDesktop App
Communications / email-server-client
Red Hat Enterprise LinuxRed Hat Inc.
On-premOS
Operating Systems / linux-distro
Debian GNU/LinuxСообщество свободного программного обеспечения
On-premOS
Operating Systems / linux-distro
SUSE Linux Enterprise Workstation ExtensionNovell Inc.
On-premOS
Operating Systems / linux-distro
РЕД ОСООО «Ред Софт»
On-premOS
Operating Systems / linux-distro
mozillaoss-projectUSConsumer Softwareaka mozilla corp.
red hat inc.commercialUSOperating Systemsaka red hat
сообщество свободного программного обеспеченияoss-projectOperating Systemsaka сообщество свободного программного обеспечения, fsf
novell inc.commercialUSOperating Systems
ооо «ред софт»commercialRUOperating Systemsaka red soft
and 6 more affected products View all →

Exploitability

Official Patch Available

References

https://www.mozilla.org/security/advisories/mfsa2021-13/
mozilla.org
https://bugzilla.mozilla.org/show_bug.cgi?id=1673240
bugzilla.mozilla.org
https://access.redhat.com/security/cve/CVE-2021-23991&#13;
access.redhat.com
and 7 more references View all →

Timeline

Published
Jun 24, 2021
Last Updated
Nov 21, 2024

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