Sandbox escape due to uninitialized memory in the DOM: Web Serial component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
CVE-2026-109745
UNRATEDCVSS · not yet scoredTrending — 4 sources updated this week
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EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- No CVSS published and no exploitation signals yet
CISA-KEV: Not listedEPSS PROB: —CVSS v2: —Exploit: None knownExposed services: Not assessed
The CVE record names the fixed release — apply it.
- CVSS v3
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- EchelonGraph score
- Not yet assessedNo source has published severity data for this CVE yet — no CVSS score from NVD or a CNA, no GitHub advisory, and it is not in CISA KEV. This is not a rating of zero; we cannot assess it yet.
- EG Score
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- EG Risk
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- EPSS PROB
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- EPSS %ILE
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- KEV
- Not listed
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it
Published
October 13, 2026
Last Modified
October 13, 2026
References (5)
- security@mozillahttps://bugzilla.mozilla.org/show_bug.cgi?id=2061784
- security@mozillahttps://www.mozilla.org/security/advisories/mfsa2026-106/
- security@mozillahttps://www.mozilla.org/security/advisories/mfsa2026-108/
- security@mozillahttps://www.mozilla.org/security/advisories/mfsa2026-109/
- security@mozillahttps://www.mozilla.org/security/advisories/mfsa2026-110/
Vendor Advisories for CVE-2026-109745(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Data Freshness Timeline
(refreshed 8× in last 7d / 8× in last 30d)
Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.
- 2026-10-13 20:08 UTCGHSA enrichmentGHSA-fhx5-x7g9-94qv
- 2026-10-13 19:24 UTCNVD update
- 2026-10-13 18:40 UTCGHSA enrichmentGHSA-fhx5-x7g9-94qv
- 2026-10-13 18:34 UTCMITRE cvelistV5
- 2026-10-13 16:30 UTCGHSA enrichmentGHSA-fhx5-x7g9-94qv
- 2026-10-13 13:25 UTCNVD update
- 2026-10-13 12:58 UTCEG score recompute
- 2026-10-13 12:54 UTCMITRE cvelistV5first tracked
Frequently asked(3)
What is CVE-2026-109745?
CVE-2026-109745 is a vulnerability whose severity is not yet rated; its CVE record was published on October 13, 2026. Sandbox escape due to uninitialized memory in the DOM: Web Serial component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
When was the CVE record for CVE-2026-109745 published?
The CVE record for CVE-2026-109745 was published on October 13, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 13, 2026; the record at its source may have been updated since.
How do I remediate CVE-2026-109745?
The CVE record for CVE-2026-109745 names the fix: "This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5." The vendor advisories EchelonGraph has for CVE-2026-109745 are linked in the Vendor Advisories panel on this page.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-109745
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