Home/CVE/When invoking protocol handlers for external protocols, a supplied parameter URL containing spaces was not properly esca
CVE

CVE-2021-43541

When invoking protocol handlers for external protocols, a supplied parameter URL containing spaces was not properly esca

When invoking protocol handlers for external protocols, a supplied parameter URL containing spaces was not properly escaped. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.

MEDIUM · CVSS 6.5 EPSS 0.00356
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules1 YARA rules0
▤

Affected Products & Versions

4
mozilla firefox< 95.0
mozilla firefox esr< 91.4.0
mozilla thunderbird< 91.4.0
debian linuxall versions
◈

Sigma Hunt Rules

1
Exact rules name this CVE ID. Product rules name an affected product in their title. Related rules cover techniques used by actors who exploited this CVE. Showing the most relevant matches; the complete related set is on the full drill-down.
producthighSQLite Firefox Profile Data DB Access
▣

Scoring & Timeline

6.5
MEDIUM · CVSS v3.1 · security@mozilla.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD08 Dec 2021 · 10:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
⚑

Vendor Advisories

26
suse-csafopenSUSE-SU-2024:14572-1
suse-csafopenSUSE-SU-2024:11669-1
suse-csafopenSUSE-SU-2024:11670-1
usnUSN-5248-1
usnUSN-5246-1
🔗

References & Sources

10
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://bugzilla.mozilla.org/show_bug.cgi?id=1696685Issue TrackingPermissions RequiredVendor Advisory
https://lists.debian.org/debian-lts-announce/2021/12/msg00030.htmlMailing ListThird Party Advisory
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.htmlMailing ListThird Party Advisory
https://security.gentoo.org/glsa/202202-03Third Party Advisory
https://security.gentoo.org/glsa/202208-14Third Party Advisory
https://www.debian.org/security/2021/dsa-5026Third Party Advisory
Intelligence Graph · click any node to traverse
CVETechnique ActorTool Family
drag to reposition · click any node to traverse · button top-right enlarges
External lookups - second-class, for what we don’t hold ourselves
NVDCVE.orgCISAVulnersExploit-DBGitHub PoCVulnCheck KEVGreyNoise
Vulnerabilities
CISA KEV catalog
CWE weaknesses
CAPEC attack patterns
Package vulnerabilities
Threat intelligence
Threat actors
Tools & malware
ATT&CK techniques
IOCs
Detection & defense
Sigma rules
YARA rules
Atomic Red Team tests
D3FEND countermeasures
Compliance
NIST 800-53
ISO 27001:2022
SOC 2 TSC
PCI-DSS v4.0
CIS Controls v8.1
About
All capabilities
Live statistics
Data sources
Privacy policy
Terms of service
threatengine.sh  ·  Open-source threat intelligence platform  ·  100+ authoritative sources  ·  Every fact traces to its origin