CVE-2026-75874

CRITICALPre-NVD 10.010.0—
EchelonGraph scoreHIGH confidence

Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-18. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 10.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 5 sources updated this week
10.0EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 10.0Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Sandbox escape in the Remote Settings Client component. This vulnerability was fixed in Firefox 154 and Thunderbird 154.

CVSS v3
10.0
EG Score
10.0(high)
EG Risk
60(Track)
EG Risk 60/100SSVC: Track

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
Severity100% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
34%
KEV
Not listed

Published

August 18, 2026

Last Modified

August 19, 2026

Advisory Details (3)

Auto-updated Aug 19, 2026
No patch confirmed yet.
generic

Security Vulnerabilities fixed in Thunderbird 154 — Mozilla

https://www.mozilla.org/security/advisories/mfsa2026-78/
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=2039972

Vendor Advisories for CVE-2026-75874(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 31× in last 7d / 31× 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.

  1. 2026-08-21 08:16 UTCGHSA enrichment
  2. 2026-08-21 04:13 UTCGHSA enrichment
  3. 2026-08-21 00:11 UTCEG score recompute
  4. 2026-08-21 00:10 UTCGHSA enrichment
  5. 2026-08-20 22:56 UTCEPSS rescore
  6. 2026-08-20 20:08 UTCGHSA enrichment
  7. 2026-08-20 16:06 UTCGHSA enrichment
  8. 2026-08-20 12:03 UTCGHSA enrichment
  9. 2026-08-20 07:55 UTCGHSA enrichment
  10. 2026-08-20 03:53 UTCGHSA enrichment
  11. 2026-08-19 23:51 UTCGHSA enrichment
  12. 2026-08-19 19:48 UTCEG score recompute
  13. 2026-08-19 19:48 UTCGHSA enrichment
  14. 2026-08-19 17:04 UTCEPSS rescore
  15. 2026-08-19 15:45 UTCGHSA enrichment
  16. 2026-08-19 12:36 UTCGHSA enrichment
  17. 2026-08-19 08:34 UTCGHSA enrichment
  18. 2026-08-19 04:31 UTCGHSA enrichment
  19. 2026-08-19 00:28 UTCEG score recompute
  20. 2026-08-19 00:27 UTCGHSA enrichment
  21. 2026-08-18 20:24 UTCGHSA enrichment
  22. 2026-08-18 19:29 UTCEG score recompute▲ 10.00
  23. 2026-08-18 19:29 UTCGHSA enrichment
  24. 2026-08-18 19:29 UTCMITRE cvelistV5CVSS v3 → 10 · severity → CRITICAL
  25. 2026-08-18 19:25 UTCGHSA enrichment
Show 6 more
  1. 2026-08-18 19:23 UTCNVD update
  2. 2026-08-18 19:06 UTCGHSA enrichment
  3. 2026-08-18 19:04 UTCMITRE cvelistV5
  4. 2026-08-18 13:19 UTCNVD update
  5. 2026-08-18 12:42 UTCEG score recompute
  6. 2026-08-18 12:41 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-75874?
CVE-2026-75874 is a critical vulnerability published on August 18, 2026. Sandbox escape in the Remote Settings Client component. This vulnerability was fixed in Firefox 154 and Thunderbird 154.
When was CVE-2026-75874 disclosed?
CVE-2026-75874 was first published in the National Vulnerability Database 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-2026-75874 actively exploited?
CVE-2026-75874 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 66.3% of all scored CVEs.
What is the CVSS score of CVE-2026-75874?
CVE-2026-75874 has a CVSS v3.1 base score of 10.0 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-75874?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-75874, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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