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firefox: Memory safety bugs fixed in Firefox 140 and Thunderbird 140

cve CVE-2025-6436 2 sources, 2 claims · Watch

Red Hat writes:
firefox: Memory safety bugs fixed in Firefox 140 and Thunderbird 140 the claim

What it is to other things

affectsmozilla/firefox
NVD
affectsmozilla/thunderbird
NVD
made_bymozilla
NVD

What each source says

PropertySourceSaidMeans here
Cvss
cvss
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receipt
Source
NVD
Its words
8.1
Read by
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Said since
2026-10-02 12:00 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
What the source handed over
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Cvss
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Its words
7.5
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Said since
2026-09-29 09:44 UTC
Last answered
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Original
open at the source
What the source handed over
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—
Product
product
NVDFirefox
receipt
Source
NVD
Its words
Firefox
Read by
field:cve.affected[].affectedData[].product
Said since
2026-10-02 12:00 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
What the source handed over
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Severity
severity
Red Hatimportant
A flaw that can easily compromise confidentiality, integrity or availability.
receipt
Source
Red Hat
Its words
important
Read by
field:severity
Said since
2026-09-29 09:44 UTC
Last answered
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Original
open at the source
What the source handed over
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high
Status
status
NVDModified
receipt
Source
NVD
Its words
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Read by
field:cve.vulnStatus
Said since
2026-10-02 12:00 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
What the source handed over
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Vendor
vendor
NVDMozilla
receipt
Source
NVD
Its words
Mozilla
Read by
field:cve.affected[].affectedData[].vendor
Said since
2026-10-02 12:00 UTC
Last answered
2026-10-05 12:24 UTC
Original
open at the source
What the source handed over
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—

vulnerability

firefox: Memory safety bugs fixed in Firefox 140 and Thunderbird 140
zetlyn/cve-redhat · 2025-06-24
cvss 7.5 severity important source
Memory safety bugs present in Firefox 139 and Thunderbird 139. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 140 and Thunderbird 140.
zetlyn/cve-nvd · 2025-06-24
cvss 8.1 product Firefox status Modified vendor Mozilla source