Stunnel: ssrf bypass in stunnel socks proxy via ipv4-mapped ipv6 loopback and unspecified addresses allows access to loopback-only services
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Mobi-Com Polska Sp. z o.o. | stunnel | unaffected |
|
||||||
| Red Hat | Red Hat Enterprise Linux 10 | affected | — | ||||||
| Red Hat | Red Hat Enterprise Linux 6 | unaffected | — | ||||||
| Red Hat | Red Hat Enterprise Linux 7 | unaffected | — | ||||||
| Red Hat | Red Hat Enterprise Linux 8 | affected | — | ||||||
| Red Hat | Red Hat Enterprise Linux 9 | affected | — |
No data.
No data.
| Vendor | Product | Versions | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Stunnel | Stunnel |
|
Vendor Workaround
To mitigate this issue, if SOCKS proxying functionality is not required, disable the "protocol = socks" configuration in "stunnel". If SOCKS proxying is necessary, restrict access to the SOCKS listener by binding it to a trusted management network or localhost, and enforce client authentication or network ACL controls. Run "stunnel" in a container or network namespace where no other services are bound to localhost, or add firewall rules to restrict outgoing connections from "stunnel" to localhost.
No CVSS v4.0
No CVSS v3.0
No CVSS v2
This CVE is not in the KEV list.
Exploit prediction score: < 1% (0.224% probability within 30 days)
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Redhat rhel Els
|
|
| CPEs | cpe:/o:redhat:enterprise_linux:6 cpe:/o:redhat:enterprise_linux:7 cpe:/o:redhat:enterprise_linux:8 cpe:/o:redhat:enterprise_linux:9 |
cpe:/a:redhat:enterprise_linux:10 cpe:/a:redhat:enterprise_linux:8 cpe:/a:redhat:enterprise_linux:9 cpe:/o:redhat:rhel_els:6 cpe:/o:redhat:rhel_els:7 |
| Vendors & Products |
Redhat rhel Els
|
| Type | Values Removed | Values Added |
|---|---|---|
| Metrics |
ssvc
|
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Stunnel
Stunnel stunnel |
|
| Vendors & Products |
Stunnel
Stunnel stunnel |
| Type | Values Removed | Values Added |
|---|---|---|
| Title | stunnel: SSRF bypass in stunnel SOCKS proxy via IPv4-mapped IPv6 loopback and unspecified addresses allows access to loopback-only services | Stunnel: ssrf bypass in stunnel socks proxy via ipv4-mapped ipv6 loopback and unspecified addresses allows access to loopback-only services |
| First Time appeared |
Redhat
Redhat enterprise Linux |
|
| CPEs | cpe:/o:redhat:enterprise_linux:10 cpe:/o:redhat:enterprise_linux:6 cpe:/o:redhat:enterprise_linux:7 cpe:/o:redhat:enterprise_linux:8 cpe:/o:redhat:enterprise_linux:9 |
|
| Vendors & Products |
Redhat
Redhat enterprise Linux |
|
| References |
|
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Title | stunnel: SSRF bypass in stunnel SOCKS proxy via IPv4-mapped IPv6 loopback and unspecified addresses allows access to loopback-only services | |
| Weaknesses | CWE-918 | |
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|