CVE-2026-16389
Tomoya Nakanishi discovered a flaw in nss, the Mozilla Network Security Service library, which may result in execution of arbitrary code if a specially crafted certificate is processed. https://security-tracker.debian.org/tracker/DSA-6403-1
CSIRTS triage
- What
- A flaw in nss may allow execution of arbitrary code if a specially crafted certificate is processed.
- Who is affected
- Users of the nss library are affected.
- Urgency
- Remediation is urgent due to the potential for arbitrary code execution.
- Action
- Update nss to the latest version to mitigate the vulnerability.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Low exploitation risk0.42% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 35% of all EPSS-scored CVEs.
Advisory coverage (6)
- high[NEW] [high] Mozilla Firefox and Firefox ESR: Multiple vulnerabilitiescert-bund · 2026-07-31
- unknownDSA-6403-1 nss - security updatedebian · 2026-07-29
- unknownMultiple vulnerabilities in Mozilla Thunderbird (July 23, 2026)cert-fr-avis · 2026-07-23
- unknownMozilla Products Multiple Vulnerabilitieshkcert · 2026-07-22
- unknownMultiple vulnerabilities in Mozilla products (July 22, 2026)cert-fr-avis · 2026-07-22
- criticalCVE-2026-16389: Incorrect boundary conditions, integer overflow in the Libraries component in NSS. This vulner…nvd · 2026-07-21
External references
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