CVE-2026-66053: Apache Thrift: Python TSSLSocket Hostname Matcher Import

mediumCVSS 5.9CVE-2026-66053

CSIRTS triage

vendor: Apache product: Thrift Authentication bypass

What: Python TSSLSocket hostname matcher import vulnerability allows improper SSL/TLS certificate validation.
Who is affected: Applications using Apache Thrift Python bindings for SSL/TLS connections.
Urgency: Medium priority with a CVSS score of 5.9; requires careful deployment review.
Action: Update Apache Thrift to a version with proper hostname matching validation.

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

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 5.9
Published: 2026-08-06
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-66053

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-2026-660530.30% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 23% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-66053	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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

mediumCVE-2026-66053: Improper Validation of Certificate with Host Mismatch vulnerability in Apache Thrift Python bi…nvd

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