CVE-2026-42764 Details
Issue summary: Receiving a QUIC initial packet with an invalid token may
trigger a NULL pointer dereference in the OpenSSL QUIC server with
address validation disabled.

Impact summary: NULL pointer dereference typically causes abnormal termination
of the affected QUIC server process and a Denial of Service.

If the address validation is disabled in the OpenSSL QUIC server
implementation, an attacker can crash the server by sending an initial
packet with an invalid or expired token.

By default, the client address validation is enabled in the OpenSSL QUIC server
implementation, which makes the default configuration not vulnerable
to this issue. However if the SSL_LISTENER_FLAG_NO_VALIDATE is used with
the SSL_new_listener() call, the address validation is disabled making the
vulnerable code reachable.

The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this
issue, as the affected code is outside the OpenSSL FIPS module boundary.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2026-42764
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
0.68 Probability of exploitation activity being observed over the next 30 days (48th percentile)
CVSS score for CVE-2026-42764
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
7.5 High
Products affected by CVE-2026-42764
OpenSSL 3.5.0
OpenSSL 3.6.2
OpenSSL 3.5.1
OpenSSL 3.6.0
OpenSSL 3.5.2
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Low
More on DVE scores

CVE-2026-42764 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 9,138 34.78%
JP 2,420 9.21%
DE 2,135 8.13%
IE 1,220 4.64%
GB 1,209 4.60%
IN 1,175 4.47%
CA 799 3.04%
FR 757 2.88%
NL 597 2.27%
KR 467 1.78%

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CVE-2026-42764 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Technology 16,730 79.86%
Telecommunications 2,081 9.93%
Education 1,295 6.18%
Government/Politics 253 1.21%
Business Services 97 0.46%
Finance 66 0.32%
Healthcare/Wellness 59 0.28%
Manufacturing 57 0.27%
Utilities 41 0.20%
Nonprofit/NGO 35 0.17%

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