CVE-2026-42764: NULL Pointer Dereference in QUIC Server Initial Packet Handling

highCVSS 7.5CVE-2026-42764

CSIRTS triage

Other

What: This vulnerability is a NULL Pointer Dereference in QUIC Server Initial Packet Handling.
Who is affected: Deployments using QUIC are affected by this vulnerability.
Urgency: Remediation is urgent due to a high severity rating.
Action: Implement necessary updates to address this vulnerability.

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

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: high — CVSS 7.5
Published: 2026-06-09
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42764

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-2026-427640.68% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 48% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-42764	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

high[UPDATE] [high] OpenSSL: Multiple Vulnerabilitiescert-bund

Recent advisories for NULL Pointer Dereference

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.

mediumCVE-2026-21901: A NULL Pointer Dereference vulnerability in the management daemon (mgd) of Juniper Networks Ju…nvd · 2026-07-09
highCVE-2026-60109: Zeek before 8.0.9 contains a null pointer dereference vulnerability in its Kerberos protocol a…nvd · 2026-07-09
unknownCVE-2026-56288: GNU patch is vulnerable to a NULL pointer dereference when processing a specially crafted unif…nvd · 2026-07-09
mediumCVE-2026-50812: A NULL pointer dereference in the SQLite Session Extension in SQLite 3.53.1 and SQLite trunk b…nvd · 2026-07-08
mediumCVE-2026-56401: Wazuh wazuh-modulesd before 5.0.0-beta3 contains a null pointer dereference vulnerability in i…nvd · 2026-07-08
mediumCVE-2026-50810: A NULL pointer dereference in smooth_parse_stream_index() in src/media_tools/mpd.c in GPAC mas…nvd · 2026-07-07