CVE catalog
CVE-2026-70367
A Server-Side Request Forgery (SSRF) bypass vulnerability exists in “stunnel” 5.79 and lower when configured in SOCKS proxy mode. This flaw allows a client to bypass intended localhost restrictions by
- Severity
- Medium · CVSS 5.4
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.16% · Oct 25, 2026
A Server-Side Request Forgery (SSRF) bypass vulnerability exists in “stunnel” 5.79 and lower when configured in SOCKS proxy mode. This flaw allows a client to bypass intended localhost restrictions by using IPv4-mapped IPv6 addresses (e.g., “::ffff:127.0.0.1”) or unspecified addresses ("0.0.0.0", "::"), enabling access to loopback-only services on the "stunnel" host that should not be network-reachable.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | stunnel4 | trixie | 3:5.74-2 | vulnerable |
| Debian | stunnel4 | bookworm | 3:5.68-2+deb12u1 | vulnerable |
| Suse | stunnel | linux enterprise module for server applications 15 sp7 | 5.70-150600.3.6.1 | fixed |
| Opensuse | stunnel | tumbleweed | 5.80-1.1 | fixed |
| Suse | stunnel | linux enterprise server 16.0 | 5.74-160000.3.1 | fixed |
| Suse | stunnel | linux enterprise server for sap applications 16.0 | 5.74-160000.3.1 | fixed |
| Opensuse | stunnel | leap 16.0 | 5.74-160000.3.1 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | stunnel4 | source | trixie | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | stunnel4 | source | bookworm | (unfixed) | not yet assigned | Not reported | Not reported |
| Suse | stunnel | rpm | linux enterprise module for server applications 15 sp7 | 5.70-150600.3.6.1 | Not reported | SUSE-SU-2026:4617-1 | Not reported |
| Opensuse | stunnel | rpm | tumbleweed | 5.80-1.1 | Not reported | OPENSUSE-SU-2026:11500-1 | Not reported |
| Suse | stunnel | rpm | linux enterprise server 16.0 | 5.74-160000.3.1 | Not reported | SUSE-SU-2026:24232-1 | Not reported |
| Suse | stunnel | rpm | linux enterprise server for sap applications 16.0 | 5.74-160000.3.1 | Not reported | SUSE-SU-2026:24232-1 | Not reported |
| Opensuse | stunnel | rpm | leap 16.0 | 5.74-160000.3.1 | Not reported | OPENSUSE-SU-2026:22088-1 | Not reported |
Notes
[trixie] stunnel4: Minor issue [bookworm] stunnel4: Minor issue
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [stunnel4]Affected
Details (2)
3:5.68-2+deb12u1· amd64 · bookwormAffected
nvd · stunnel4 · debian · bookworm; nvd · stunnel4 · debian · 12
3:5.68-2+deb12u1· arm64 · bookwormAffected
nvd · stunnel4 · debian · bookworm; nvd · stunnel4 · debian · 12
[Debian 13 (Trixie)]
- [stunnel4]Affected
Details (2)
3:5.74-2· amd64 · trixieAffected
nvd · stunnel4 · debian · 13
3:5.74-2· arm64 · trixieAffected
nvd · stunnel4 · debian · 13
[openSUSE Tumbleweed]
- [stunnel-doc]Unknown
Source package: [stunnel]
Details (1)
5.80-1.1· noarch · tumbleweedUnknown · Fixed:
5.80-1.1Version impact unknown
nvd · stunnel · opensuse · tumbleweed
- [stunnel]Fixed
Source package: [stunnel]
Details (1)
5.80-1.1· x86_64 · tumbleweedFixed · Fixed:
5.80-1.1nvd · stunnel · opensuse · tumbleweed
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/opensuse-su-2026_11500-1.json]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-70367]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-70367]
- [https://osv.dev/vulnerability/SUSE-SU-2026:24232-1]
- [https://osv.dev/vulnerability/SUSE-SU-2026:4617-1]
- [https://osv.dev/vulnerability/openSUSE-SU-2026:11500-1]
- [https://osv.dev/vulnerability/openSUSE-SU-2026:22088-1]
- [https://security-tracker.debian.org/tracker/CVE-2026-70367]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-70367.json]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]