CVE-2026-74971

MEDIUMPre-NVD 4.34.3—
EchelonGraph scoreMEDIUM confidence

Score 4.3 from GitHub Security Advisory published 2026-08-18. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 4.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 4 sources updated this week
4.3EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 4.3Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Information disclosure in the DOM: UI Events & Focus Handling component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.

CVSS v3
4.3
EG Score
4.3MEDIUMmedium confidence
EG Risk
19
EG Risk 19/100CISA SSVC

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity43% × 45%
Exploitation0% × 40%
Automatability0% × 15%
CISA SSVC: Track at every mission impact level.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.3%
EPSS %ILE
25th
KEV
Not listed

CISA SSVCTrack at every mission impact level.

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

August 18, 2026

Last Modified

August 19, 2026

Advisory Details (7)

Auto-updated Aug 18, 2026
Patch available.
generic

Security Vulnerabilities fixed in Thunderbird 153.1 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-80/
generic

Security Vulnerabilities fixed in Thunderbird 140.14 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-79/
generic

Security Vulnerabilities fixed in Thunderbird 154 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-78/
generic

Security Vulnerabilities fixed in Firefox ESR 153.1 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-77/
generic

Security Vulnerabilities fixed in Firefox ESR 140.14 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-76/
generic

Security Vulnerabilities fixed in Firefox 154 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-74/
generic

Access Denied

https://bugzilla.mozilla.org/show_bug.cgi?id=2057204

Vendor Advisories for CVE-2026-74971(16)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(21)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatfirefox-0:140.14.0-1.el9_22026-09-09redhat
redhatthunderbird-0:140.14.0-1.el8_82026-09-09redhat
redhatthunderbird-0:140.14.0-1.el8_62026-09-09redhat
redhatthunderbird-0:140.14.0-1.el8_42026-09-09redhat
redhatthunderbird-0:140.14.0-1.el9_22026-09-09redhat
redhatthunderbird-0:140.14.0-1.el9_82026-09-08redhat
redhatthunderbird-0:140.14.0-1.el9_62026-09-08redhat
redhatfirefox-0:140.14.0-1.el10_02026-09-08redhat
redhatthunderbird-0:140.14.0-1.el8_102026-09-08redhat
redhatthunderbird-0:140.14.0-1.el9_42026-09-08redhat
redhatfirefox-0:140.14.0-1.el9_62026-09-08redhat
redhatfirefox-0:140.14.0-1.el7_92026-09-08redhat
redhatfirefox-0:140.14.0-1.el8_42026-09-08redhat
redhatfirefox-0:140.14.0-1.el8_62026-09-08redhat
redhatthunderbird-0:140.14.0-1.el10_22026-09-08redhat
redhatfirefox-0:140.14.0-1.el8_82026-09-08redhat
redhatfirefox-0:140.14.0-1.el9_42026-09-08redhat
redhatthunderbird-0:140.14.0-1.el10_02026-09-08redhat
redhatfirefox-0:140.14.0-1.el9_82026-08-24redhat
redhatfirefox-0:140.14.0-1.el10_22026-08-24redhat
redhatfirefox-0:140.14.0-1.el8_102026-08-24redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(6 across 3 ecosystems)
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr102.11.0esr-1 ... 140.9.1esr-1~deb13u1 (195 versions)
  • every version up to 140.14.0esr-1~deb12u1: fixed in 140.14.0esr-1~deb12u1
—
thunderbird1:102.11.0-1 ... 1:140.9.1esr-1~deb13u1 (224 versions)
  • every version up to 1:140.14.0esr-1~deb12u1: fixed in 1:140.14.0esr-1~deb12u1
—
Debian:13(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr128.13.0esr-1 ... 140.9.1esr-1~deb13u1 (71 versions)
  • every version up to 140.14.0esr-1~deb13u1: fixed in 140.14.0esr-1~deb13u1
—
thunderbird1:128.13.0esr-1 ... 1:140.9.1esr-1~deb13u1 (80 versions)
  • every version up to 1:140.14.0esr-1~deb13u1: fixed in 1:140.14.0esr-1~deb13u1
—
Debian:14(2)
PackageVulnerable rangeFix by version rangeDependents
firefox-esr128.13.0esr-1 ... 140.9.1esr-1~deb13u1 (72 versions)
  • every version up to 140.14.0esr-2: fixed in 140.14.0esr-2
—
thunderbird1:128.13.0esr-1 ... 1:140.9.1esr-1~deb13u1 (81 versions)
  • every version up to 1:140.14.0esr-1: fixed in 1:140.14.0esr-1
—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Additional Vendor Advisories

(6)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 22× in last 7d / 103× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 174 total refreshes for this CVE.

  1. 2026-10-04 23:22 UTCEPSS rescore
  2. 2026-10-04 21:45 UTCVendor advisory
  3. 2026-10-04 21:45 UTCGHSA enrichment
  4. 2026-10-03 17:43 UTCEG score recompute
  5. 2026-10-03 17:43 UTCVendor advisory
  6. 2026-10-03 17:43 UTCGHSA enrichment
  7. 2026-10-03 14:26 UTCEPSS rescore
  8. 2026-10-02 09:13 UTCEG score recompute
  9. 2026-10-02 09:13 UTCVendor advisory
  10. 2026-10-02 09:13 UTCGHSA enrichment
  11. 2026-10-01 19:50 UTCEPSS rescore
  12. 2026-10-01 09:32 UTCEG score recompute
  13. 2026-10-01 09:32 UTCVendor advisory
  14. 2026-10-01 09:32 UTCGHSA enrichment
  15. 2026-09-30 09:54 UTCEG score recompute
  16. 2026-09-30 09:54 UTCVendor advisory
  17. 2026-09-30 09:54 UTCGHSA enrichment
  18. 2026-09-29 15:24 UTCEPSS rescore
  19. 2026-09-29 07:18 UTCEG score recompute
  20. 2026-09-29 07:18 UTCVendor advisory
  21. 2026-09-29 07:18 UTCGHSA enrichment
  22. 2026-09-28 13:52 UTCEPSS rescore
  23. 2026-09-28 07:38 UTCEG score recompute
  24. 2026-09-28 07:38 UTCVendor advisory
  25. 2026-09-28 07:38 UTCGHSA enrichment
Show 75 more
  1. 2026-09-27 13:48 UTCEPSS rescore
  2. 2026-09-27 08:01 UTCEG score recompute
  3. 2026-09-27 08:01 UTCVendor advisory
  4. 2026-09-27 08:01 UTCGHSA enrichment
  5. 2026-09-26 15:59 UTCEPSS rescore
  6. 2026-09-26 00:28 UTCEPSS rescore
  7. 2026-09-25 01:41 UTCEG score recompute
  8. 2026-09-25 01:41 UTCVendor advisory
  9. 2026-09-25 01:41 UTCGHSA enrichment
  10. 2026-09-24 14:04 UTCEPSS rescore
  11. 2026-09-23 22:37 UTCEG score recompute
  12. 2026-09-23 22:37 UTCVendor advisory
  13. 2026-09-23 22:37 UTCGHSA enrichment
  14. 2026-09-23 17:54 UTCEPSS rescore
  15. 2026-09-22 23:00 UTCEG score recompute
  16. 2026-09-22 23:00 UTCVendor advisory
  17. 2026-09-22 23:00 UTCGHSA enrichment
  18. 2026-09-22 16:01 UTCEPSS rescore
  19. 2026-09-21 23:23 UTCEG score recompute
  20. 2026-09-21 23:23 UTCVendor advisory
  21. 2026-09-21 23:23 UTCGHSA enrichment
  22. 2026-09-21 21:09 UTCEPSS rescore
  23. 2026-09-20 23:45 UTCEG score recompute
  24. 2026-09-20 23:45 UTCVendor advisory
  25. 2026-09-20 23:45 UTCGHSA enrichment
  26. 2026-09-20 20:16 UTCEPSS rescore
  27. 2026-09-19 23:31 UTCEG score recompute
  28. 2026-09-19 23:31 UTCVendor advisory
  29. 2026-09-19 23:31 UTCGHSA enrichment
  30. 2026-09-18 23:53 UTCEG score recompute
  31. 2026-09-18 23:53 UTCVendor advisory
  32. 2026-09-18 23:53 UTCGHSA enrichment
  33. 2026-09-18 19:28 UTCEPSS rescore
  34. 2026-09-18 00:16 UTCEG score recompute
  35. 2026-09-18 00:16 UTCVendor advisory
  36. 2026-09-18 00:16 UTCGHSA enrichment
  37. 2026-09-17 00:35 UTCEG score recompute
  38. 2026-09-17 00:35 UTCVendor advisory
  39. 2026-09-17 00:35 UTCGHSA enrichment
  40. 2026-09-16 14:08 UTCEPSS rescore
  41. 2026-09-16 05:15 UTCEPSS rescore
  42. 2026-09-16 00:57 UTCEG score recompute
  43. 2026-09-16 00:57 UTCVendor advisory
  44. 2026-09-16 00:57 UTCGHSA enrichment
  45. 2026-09-15 03:12 UTCEPSS rescore
  46. 2026-09-15 01:19 UTCVendor advisory
  47. 2026-09-15 01:19 UTCGHSA enrichment
  48. 2026-09-14 01:42 UTCEG score recompute
  49. 2026-09-14 01:42 UTCVendor advisory
  50. 2026-09-14 01:42 UTCGHSA enrichment
  51. 2026-09-13 02:04 UTCEG score recompute
  52. 2026-09-13 02:04 UTCVendor advisory
  53. 2026-09-13 02:04 UTCGHSA enrichment
  54. 2026-09-12 15:02 UTCEPSS rescore
  55. 2026-09-12 02:26 UTCEG score recompute
  56. 2026-09-12 02:26 UTCVendor advisory
  57. 2026-09-12 02:26 UTCGHSA enrichment
  58. 2026-09-11 14:53 UTCEPSS rescore
  59. 2026-09-11 02:48 UTCEG score recompute
  60. 2026-09-11 02:48 UTCVendor advisory
  61. 2026-09-11 02:48 UTCGHSA enrichment
  62. 2026-09-10 09:35 UTCEPSS rescore
  63. 2026-09-10 03:10 UTCVendor advisory
  64. 2026-09-10 03:10 UTCGHSA enrichment
  65. 2026-09-09 03:32 UTCEG score recompute
  66. 2026-09-09 03:32 UTCVendor advisory
  67. 2026-09-09 03:32 UTCGHSA enrichment
  68. 2026-09-08 22:01 UTCEPSS rescore
  69. 2026-09-07 16:10 UTCEG score recompute
  70. 2026-09-07 16:10 UTCVendor advisory
  71. 2026-09-07 16:10 UTCGHSA enrichment
  72. 2026-09-06 15:27 UTCEG score recompute
  73. 2026-09-06 15:27 UTCVendor advisory
  74. 2026-09-06 15:27 UTCGHSA enrichment
  75. 2026-09-06 13:48 UTCEPSS rescore

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-74971?
CVE-2026-74971 is a medium vulnerability published on August 18, 2026. Information disclosure in the DOM: UI Events & Focus Handling component. This vulnerability was fixed in Firefox 154, Firefox ESR 140.14, Firefox ESR 153.1, Thunderbird 154, Thunderbird 140.14, and Thunderbird 153.1.
When was CVE-2026-74971 disclosed?
CVE-2026-74971 was first published on August 18, 2026, with the most recent update on August 19, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-74971 actively exploited?
CVE-2026-74971 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (25th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-74971?
CVE-2026-74971 has a CVSS v3.1 base score of 4.3 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-74971?
A fix for CVE-2026-74971 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-74971 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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