Vulnerability-Lookup

OPENSUSE-SU-2026:22088-1

Vulnerability from csaf_opensuse - Published: 2026-10-12 08:44 - Updated: 2026-10-19 17:25

Summary

Security update for stunnel

Severity

Moderate

Notes

Title of the patch: Security update for stunnel

Description of the patch: This update for stunnel fixes the following issues: - CVE-2026-70367: incomplete IP address filtering in SOCKS proxy mode can allow localhost restriction bypasses (bsc#1274207). - CVE-2026-70368: oversized log messages in logging routines can cause stack out-of-bounds reads (bsc#1274206).

Patchnames: openSUSE-Leap-16.0-1901

CVE-2026-70367

5.4 (Medium)


                
                  CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

Affected products

Recommended 5 products

Product	Version	Remediation
Unresolved product id: openSUSE Leap 16.0:stunnel-0:5.74-160000.3.1.aarch64	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:stunnel-0:5.74-160000.3.1.ppc64le	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:stunnel-0:5.74-160000.3.1.s390x	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:stunnel-0:5.74-160000.3.1.x86_64	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:stunnel-doc-0:5.74-160000.3.1.noarch	—	Vendor Fix

Threats

Impact moderate

CVE-2026-70368

6.5 (Medium)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L

Affected products

Recommended 5 products, the same list as for CVE-2026-70367

Threats

Impact moderate

References

10 references

URL	Category
https://www.suse.com/support/security/rating/	external
https://ftp.suse.com/pub/projects/security/csaf/o…	self
https://bugzilla.suse.com/1274206	self
https://bugzilla.suse.com/1274207	self
https://www.suse.com/security/cve/CVE-2026-70367/	self
https://www.suse.com/security/cve/CVE-2026-70368/	self
https://www.suse.com/security/cve/CVE-2026-70367	external
https://bugzilla.suse.com/1274207	external
https://www.suse.com/security/cve/CVE-2026-70368	external
https://bugzilla.suse.com/1274206	external

JSON

To clipboard

{
  "document": {
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      "text": "moderate"
    },
    "category": "csaf_security_advisory",
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        "text": "This update for stunnel fixes the following issues:\n\n- CVE-2026-70367: incomplete IP address filtering in SOCKS proxy mode can allow localhost restriction bypasses\n  (bsc#1274207).\n- CVE-2026-70368: oversized log messages in logging routines can cause stack out-of-bounds reads (bsc#1274206).\n",
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            ],
            "category": "product_family",
            "name": "SUSE Linux Enterprise"
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        ],
        "category": "vendor",
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          "category": "general",
          "text": "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.",
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}

CVE-2026-70367 (GCVE-0-2026-70367)

Vulnerability from cvelistv5 – Published: 2026-08-04 13:52 – Updated: 2026-08-06 07:28

Title

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

Summary

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.

Severity

5.4 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-04 14:50 UTC

CWE

CWE-918 - Server-Side Request Forgery (SSRF)

Assigner

redhat CNA under the redhat root

CNA scorecard B 82/100 over 1035 records in the last 180 days details

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-70367	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2462083	issue-trackingx_refsource_REDHAT

Impacted products

6 products

Vendor	Product	Version
Mobi-Com Polska Sp. z o.o.	stunnel	Affected: 5.25 , < 5.80 (custom)
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Date Public

2026-08-04 10:29

Credits

This issue was discovered by Found by AISLE in partnership with Red Hat.

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-70367",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-04T14:50:26.922087Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-04T14:50:38.160Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2462083"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "stunnel",
          "repo": "https://github.com/mtrojnar/stunnel",
          "vendor": "Mobi-Com Polska Sp. z o.o.",
          "versions": [
            {
              "lessThan": "5.80",
              "status": "affected",
              "version": "5.25",
              "versionType": "custom"
            }
          ]
        },
        {
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:10"
          ],
          "defaultStatus": "affected",
          "packageName": "stunnel",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
        {
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CVE-2026-70368 (GCVE-0-2026-70368)

Vulnerability from cvelistv5 – Published: 2026-08-04 13:52 – Updated: 2026-08-06 07:33

Title

Stunnel: stack-based out-of-bounds read/write in stunnel s_vlog via oversized log message

Summary

A stack-based out-of-bounds read vulnerability exists in the "s_vlog" function of stunnel, when handling oversized log messages via "vsnprintf". A remote attacker with network access to a stunnel service can send protocol inputs that trigger a log message longer than 1024 bytes, leading to an out-of-bounds stack read and a potential crash. In certain corner cases, the same vulnerability could be used to replace a series of trailing "\n" characters with "\0".

Severity

6.5 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-04 14:21 UTC

CWE

CWE-125 - Out-of-bounds Read

Assigner

redhat CNA under the redhat root

CNA scorecard B 82/100 over 1035 records in the last 180 days details

References

2 references

URL	Tags
https://access.redhat.com/security/cve/CVE-2026-70368	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2462029	issue-trackingx_refsource_REDHAT

Impacted products

6 products

Vendor	Product	Version
Mobi-Com Polska Sp. z o.o.	stunnel	Affected: 5.68 , < 5.80 (custom)
Red Hat	Red Hat Enterprise Linux 10	cpe:/o:redhat:enterprise_linux:10
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9

Date Public

2026-08-04 10:30

Credits

This issue was discovered by Found by AISLE in partnership with Red Hat.

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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OPENSUSE-SU-2026:22088-1

CVE-2026-70367 (GCVE-0-2026-70367)

CVE-2026-70368 (GCVE-0-2026-70368)

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