Staging Environment: Content and features may be unstable or change without notice.
Search for vulnerabilities
Vulnerability details: VCID-qd4e-g5zv-1ucf
Vulnerability ID VCID-qd4e-g5zv-1ucf
Aliases CVE-2021-43539
Summary Multiple vulnerabilities have been found in Mozilla Thunderbird, the worst of which could result in the arbitrary execution of code.
Status Published
Exploitability 0.5
Weighted Severity 8.0
Risk 4.0
Affected and Fixed Packages Package Details
Weaknesses (1)
CWE-416 Use After Free
System Score Found at
cvssv3 8.8 https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-43539.json
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
epss 0.00967 https://api.first.org/data/v1/epss?cve=CVE-2021-43539
cvssv3.1 7.5 https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
archlinux High https://security.archlinux.org/AVG-2606
archlinux High https://security.archlinux.org/AVG-2608
generic_textual high https://www.mozilla.org/en-US/security/advisories/mfsa2021-52
generic_textual high https://www.mozilla.org/en-US/security/advisories/mfsa2021-53
generic_textual high https://www.mozilla.org/en-US/security/advisories/mfsa2021-54
Reference id Reference type URL
https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-43539.json
https://api.first.org/data/v1/epss?cve=CVE-2021-43539
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38496
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38500
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38502
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38503
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38504
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38506
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38507
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38508
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-38509
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-4126
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-4129
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43528
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43529
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43534
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43535
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43536
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43537
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43538
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43539
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43541
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43542
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43543
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43545
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-43546
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44538
https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
2030110 https://bugzilla.redhat.com/show_bug.cgi?id=2030110
ASA-202112-8 https://security.archlinux.org/ASA-202112-8
ASA-202112-9 https://security.archlinux.org/ASA-202112-9
AVG-2606 https://security.archlinux.org/AVG-2606
AVG-2608 https://security.archlinux.org/AVG-2608
GLSA-202202-03 https://security.gentoo.org/glsa/202202-03
GLSA-202208-14 https://security.gentoo.org/glsa/202208-14
mfsa2021-52 https://www.mozilla.org/en-US/security/advisories/mfsa2021-52
mfsa2021-53 https://www.mozilla.org/en-US/security/advisories/mfsa2021-53
mfsa2021-54 https://www.mozilla.org/en-US/security/advisories/mfsa2021-54
RHSA-2021:5013 https://access.redhat.com/errata/RHSA-2021:5013
RHSA-2021:5014 https://access.redhat.com/errata/RHSA-2021:5014
RHSA-2021:5015 https://access.redhat.com/errata/RHSA-2021:5015
RHSA-2021:5016 https://access.redhat.com/errata/RHSA-2021:5016
RHSA-2021:5017 https://access.redhat.com/errata/RHSA-2021:5017
RHSA-2021:5045 https://access.redhat.com/errata/RHSA-2021:5045
RHSA-2021:5046 https://access.redhat.com/errata/RHSA-2021:5046
RHSA-2021:5047 https://access.redhat.com/errata/RHSA-2021:5047
RHSA-2021:5048 https://access.redhat.com/errata/RHSA-2021:5048
RHSA-2021:5055 https://access.redhat.com/errata/RHSA-2021:5055
USN-5186-1 https://usn.ubuntu.com/5186-1/
USN-5246-1 https://usn.ubuntu.com/5246-1/
USN-5248-1 https://usn.ubuntu.com/5248-1/
No exploits are available.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Found at https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-43539.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H Found at https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Exploit Prediction Scoring System (EPSS)
Percentile 0.76522
EPSS Score 0.00967
Published At April 1, 2026, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2026-04-01T12:58:34.288944+00:00 Gentoo Importer Import https://security.gentoo.org/glsa/202208-14 38.0.0