[UPDATE] [medium] Mozilla Firefox and Firefox ESR: Multiple vulnerabilities

mediumCVE-2026-8090 CVE-2026-8091 CVE-2026-8092 CVE-2026-8093 CVE-2026-8094

An attacker can exploit multiple vulnerabilities in Mozilla Firefox and Mozilla Firefox ESR to conduct an unspecified attack and execute arbitrary program code.

CSIRTS triage

vendor: Mozilla product: Mozilla Firefox and Firefox ESROther

What: Multiple vulnerabilities can be exploited to conduct an unspecified attack and execute arbitrary program code.
Who is affected: Users of Mozilla Firefox and Firefox ESR.
Urgency: Remediation is medium urgency due to the potential for arbitrary code execution.
Action: Update to the latest version of Mozilla Firefox and Firefox ESR.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: CERT-Bund (BSI) Security Advisories (DE · national-cert · site)
Severity: medium
Published: 2026-07-21
Exploitation: Not in CISA KEV at last sync
Language: Machine-translated to English — verify against the original

Original advisory: https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-1427

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-80900.32% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 24% of all scored CVEs.
Low exploitation riskCVE-2026-80910.47% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 38% of all scored CVEs.
Low exploitation riskCVE-2026-80920.38% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 31% of all scored CVEs.
Low exploitation riskCVE-2026-80930.32% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 25% of all scored CVEs.
Low exploitation riskCVE-2026-80940.45% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 37% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-8090	coverage & exploitation status	NVD · CVE.org
CVE-2026-8091	coverage & exploitation status	NVD · CVE.org
CVE-2026-8092	coverage & exploitation status	NVD · CVE.org
CVE-2026-8093	coverage & exploitation status	NVD · CVE.org
CVE-2026-8094	coverage & exploitation status	NVD · CVE.org

Recent advisories for Mozilla Firefox and

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

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