CVE-2026-35188 Details
Issue summary: A malicious server can exploit TLS OCSP stapling by delivering
a crafted response through the status_request extension, triggering a
double-free in the client's certificate verification path.

Impact summary: Successful exploitation allows an attacker to corrupt heap
memory via a double-free, potentially leading to a Denial of Service or
possibly an attacker controlled code execution or other undefined behavior.

If OCSP stapling is enabled and the TLS client connects to a malicious server,
a crafted OCSP stapled response can trigger a double free in the TLS client
when the stapled response is checked.

The OCSP stapling is not enabled by default. Reliable code execution
through a double-free is technically complex and highly environment-dependent
but the Denial of Service impact is straightforward to achieve, warranting
Moderate severity.

No FIPS modules are 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-2026-35188
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%).
0.24 Probability of exploitation activity being observed over the next 30 days (16th percentile)
CVSS score for CVE-2026-35188
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.
5 Medium
Products affected by CVE-2026-35188
OpenSSL 3.6.2
OpenSSL 3.6.0
OpenSSL 3.6.1
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-2026-35188 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 327 20.17%
DE 168 10.36%
RU 139 8.57%
JP 120 7.40%
CH 69 4.26%
FR 66 4.07%
GB 58 3.58%
CA 56 3.45%
KR 47 2.90%
ES 40 2.47%

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CVE-2026-35188 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 522 52.10%
Telecommunications 278 27.74%
Education 58 5.79%
Government/Politics 37 3.69%
Healthcare/Wellness 19 1.90%
Business Services 16 1.60%
Manufacturing 14 1.40%
Energy/Resources 9 0.90%
Finance 8 0.80%
Transportation 8 0.80%

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