Stunnel: ssrf bypass in stunnel socks proxy via ipv4-mapped ipv6 loopback and unspecified addresses allows access to loopback-only services

Mariner

Read the vendor bulletin Get alerts for azl3 stunnel 5.74-1 on Azure Linux

5.4CVSS out of 10Medium severity

Scope

What the vendor says is affected

azl3 stunnel 5.74-1 on Azure Linux 3.0

Timeline

When this advisory changed

Aug 7, 2026 at 1:19 AM UTC
Published by Microsoft Security Response Center
The publication date reported by the vendor.
Aug 20, 2026 at 6:50 PM UTC
Added to SecurityAlert
We collected the advisory from the official source.
Sep 6, 2026 at 6:25 AM UTC
Confirmed at the source
Our collector saw this advisory during a later source check.

Vulnerabilities

CVEs named in this advisory

CVE-2026-70367View CVSS, KEV, EPSS, and threat context

Source

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Vendor: Microsoft Security Response Center
Advisory ID: CVE-2026-70367
Last source check: Sep 13, 2026 at 2:40 AM UTC

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Watch azl3 stunnel 5.74-1 on Azure Linux

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What the vendor says is affected

When this advisory changed

CVEs named in this advisory

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