CVE-2021-43543: debian debian_linux Cross-site Scripting
CVSS: 6.1v3.1MediumModified
AliasesUBUNTU-CVE-2021-43543DEBIAN-CVE-2021-43543
Published 08-12-2021Last modified 04-08-2024
Vulnerability summary
CVE-2021-43543 is a medium (CVSS 6.1) Cross-site Scripting vulnerability in debian debian_linux. EPSS estimates a 1.45% chance of exploitation in the next 30 days, higher than 73% of scored vulnerabilities.
CVSS score
6.1/10
010
Medium · v3.1 (NVD)EPSS score
1.45%
0%100%
Low · +0.10 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 30 · Related 14DLA-2863-1DLA-2874-1DSA-5026-1DSA-5034-1MGASA-2021-0551MGASA-2021-0554OPENSUSE-SU-2021:1575-1OPENSUSE-SU-2021:1635-1OPENSUSE-SU-2021:3993-1OPENSUSE-SU-2021:4150-1OPENSUSE-SU-2024:11669-1OPENSUSE-SU-2024:11670-1OPENSUSE-SU-2024:14572-1RHSA-2021:5013RHSA-2021:5014RHSA-2021:5015RHSA-2021:5016RHSA-2021:5017RHSA-2021:5045RHSA-2021:5046RHSA-2021:5047RHSA-2021:5048RHSA-2021:5055SUSE-SU-2021:14859-1SUSE-SU-2021:3993-1SUSE-SU-2021:3995-1SUSE-SU-2021:4000-1SUSE-SU-2021:4150-1USN-5186-1USN-5248-1
Timeline
- 08-12-2021PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
Documents loaded with the CSP sandbox directive could have escaped the sandbox's script restriction by embedding additional content. This vulnerability affects Thunderbird < 91.4.0, Firefox ESR < 91.4.0, and Firefox < 95.
CVSS metrics
4 scores · 3 sources · 2 versionsMedium 6.1Preferred score · NVD (NIST)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:NSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated6.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- OSV · DebianEcosystem advisory · calculated6.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Medium 4.3Preferred score · NVD (NIST)
AV:N/AC:M/Au:N/C:N/I:P/A:NSourcesSingle source
EPSS trend
Probability
1.45%
Chance of exploitation in the next 30 days
Percentile
73%
Versus all other CVEs
30-day change
+0.10 pp
From 1.35% on 20-09-2026
20-09-202620-10-2026
EPSS score1.45%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu6 products
- firefox< 95.0+build1-0ubuntu0.18.04.1 | < 95.0+build1-0ubuntu0.20.04.1 | < 95.0+build1-0ubuntu1
- mozjs38All versions (No fix recorded)
- mozjs52All versions (No fix recorded)
- mozjs68All versions (No fix recorded)
- mozjs78All versions (No fix recorded)
Debian3 products
- firefox-esr< 91.4.0esr-1
- thunderbird< 1:91.4.0-1
- debian_linuxEOL9.0 | 10.0 | 11.0
Mozilla3 products
- firefox≥ unspecified, < 95 | < 95.0
- firefox_esr≥ unspecified, < 91.4.0 | < 91.4.0
- thunderbird≥ unspecified, < 91.4.0 | < 91.4.0
3 vendors · 12 products
References
19 links- bugzilla.mozilla.org/show_bug.cgi?id=1738418X Refsource MISCIssue TrackingPermissions RequiredVendor Advisory
- lists.debian.org/debian-lts-announce/2021/12/msg00030.htmlMailing ListX Refsource MLISTThird Party Advisory
- lists.debian.org/debian-lts-announce/2022/01/msg00001.htmlMailing ListX Refsource MLISTThird Party Advisory