{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-20230 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2021-20230 is a high-severity authentication bypass vulnerability in stunnel, published on 23 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-20230 and fix it if it is affected.\n\nWhat it is: CVE-2021-20230 is a high-severity authentication bypass vulnerability in stunnel, published on 23 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-20230 in the wild and no public exploit code.\n\nAffected product: stunnel. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2021-20230/ (Markdown: https://insights.sbomify.com/CVE-2021-20230/index.md)","id":"CVE-2021-20230","markdown":"https://insights.sbomify.com/CVE-2021-20230/index.md","name":"CVE-2021-20230","record":{"aliases":["ALSA-2021:0618","AZL-7375","CLSA-2023-1689701258","DEBIAN-CVE-2021-20230","GHSA-wwrq-59mq-v8w2","MGASA-2021-0284","RHSA-2021:0618","RHSA-2021:0619","RHSA-2021:0620","RLSA-2021:0618","SUSE-SU-2021:0772-1","SUSE-SU-2021:1465-1","UBUNTU-CVE-2021-20230","USN-6901-1","openSUSE-SU-2021:0409-1"],"analysis":{"component_type":"server_software","fix_type":"upgrade","impacts":["data_read","security_bypass"],"network_reachable":"yes","non_default_config":true,"product_category":"SSL/TLS tunneling software","requires_auth":"none","summary":"Attackers with valid CA-signed certificates can bypass redirect restrictions to access tunneled services, compromising confidentiality.","user_interaction":"not_required","vuln_class":"auth_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"redhat","cpe":[{"product":"stunnel","vendor":"stunnel"}],"cvss":{"score":7.5,"severity":"high","source":"nvd","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-295","name":"Improper Certificate Validation"}],"description":"A flaw was found in stunnel before 5.57, where it improperly validates client certificates when it is configured to use both redirect and verifyChain options. This flaw allows an attacker with a certificate signed by a Certificate Authority, which is not the one accepted by the stunnel server, to access the tunneled service instead of being redirected to the address specified in the redirect option. The highest threat from this vulnerability is to confidentiality.","ecosystems":["AlmaLinux:8","Red Hat:enterprise_linux:8::baseos","Red Hat:rhel_eus:8.1::baseos","Red Hat:rhel_eus:8.2::baseos","Rocky Linux:8","SUSE:Enterprise Storage 6","SUSE:Linux Enterprise High Performance Computing 15 SP1-ESPOS","SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS","SUSE:Linux Enterprise High Performance Computing 15-ESPOS","SUSE:Linux Enterprise High Performance Computing 15-LTSS","SUSE:Linux Enterprise Module for Server Applications 15 SP2","SUSE:Linux Enterprise Server 15 SP1-BCL","SUSE:Linux Enterprise Server 15 SP1-LTSS","SUSE:Linux Enterprise Server 15-LTSS","SUSE:Linux Enterprise Server for SAP Applications 15","SUSE:Linux Enterprise Server for SAP Applications 15 SP1","SUSE:Manager Proxy 4.0","SUSE:Manager Retail Branch Server 4.0","SUSE:Manager Server 4.0","openSUSE:Leap 15.2"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Auth bypass in stunnel","id":"CVE-2021-20230","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"auth_bypass","year":"2021"},"n_packages":26,"n_references":3,"next":{"headline":"Use after free in gnutls","id":"CVE-2021-20231"},"packages":[{"ecosystem":"AlmaLinux:8","fixed":["5.56-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/almalinux/stunnel","source":"ALSA-2021:0618"},{"ecosystem":"Red Hat:enterprise_linux:8::baseos","fixed":["0:5.56-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/redhat/stunnel","source":"RHSA-2021:0618"},{"ecosystem":"Red Hat:enterprise_linux:8::baseos","fixed":["0:5.56-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"stunnel-debuginfo","purl":"pkg:rpm/redhat/stunnel-debuginfo","source":"RHSA-2021:0618"},{"ecosystem":"Red Hat:enterprise_linux:8::baseos","fixed":["0:5.56-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"stunnel-debugsource","purl":"pkg:rpm/redhat/stunnel-debugsource","source":"RHSA-2021:0618"},{"ecosystem":"Red Hat:rhel_eus:8.1::baseos","fixed":["0:5.48-6.el8_1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/redhat/stunnel","source":"RHSA-2021:0620"},{"ecosystem":"Red Hat:rhel_eus:8.1::baseos","fixed":["0:5.48-6.el8_1"],"introduced":["0"],"last_affected":[],"package":"stunnel-debuginfo","purl":"pkg:rpm/redhat/stunnel-debuginfo","source":"RHSA-2021:0620"},{"ecosystem":"Red Hat:rhel_eus:8.1::baseos","fixed":["0:5.48-6.el8_1"],"introduced":["0"],"last_affected":[],"package":"stunnel-debugsource","purl":"pkg:rpm/redhat/stunnel-debugsource","source":"RHSA-2021:0620"},{"ecosystem":"Red Hat:rhel_eus:8.2::baseos","fixed":["0:5.48-6.el8_2"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/redhat/stunnel","source":"RHSA-2021:0619"},{"ecosystem":"Red Hat:rhel_eus:8.2::baseos","fixed":["0:5.48-6.el8_2"],"introduced":["0"],"last_affected":[],"package":"stunnel-debuginfo","purl":"pkg:rpm/redhat/stunnel-debuginfo","source":"RHSA-2021:0619"},{"ecosystem":"Red Hat:rhel_eus:8.2::baseos","fixed":["0:5.48-6.el8_2"],"introduced":["0"],"last_affected":[],"package":"stunnel-debugsource","purl":"pkg:rpm/redhat/stunnel-debugsource","source":"RHSA-2021:0619"},{"ecosystem":"Rocky Linux:8","fixed":["0:5.56-5.el8_3"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/rocky-linux/stunnel?distro=rocky-linux-8\u0026epoch=0","source":"RLSA-2021:0618"},{"ecosystem":"SUSE:Enterprise Storage 6","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Enterprise%20Storage%206","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP1-ESPOS","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP1-ESPOS","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP1-LTSS","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP1-LTSS","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Linux Enterprise High Performance Computing 15-ESPOS","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015-ESPOS","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Linux Enterprise High Performance Computing 15-LTSS","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015-LTSS","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Linux Enterprise Module for Server Applications 15 SP2","fixed":["5.57-3.11.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20Module%20for%20Server%20Applications%2015%20SP2","source":"SUSE-SU-2021:0772-1"},{"ecosystem":"SUSE:Linux Enterprise Server 15 SP1-BCL","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP1-BCL","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Linux Enterprise Server 15 SP1-LTSS","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP1-LTSS","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Linux Enterprise Server 15-LTSS","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20Server%2015-LTSS","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 15","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 15 SP1","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP1","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Manager Proxy 4.0","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Manager%20Proxy%204.0","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Manager Retail Branch Server 4.0","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Manager%20Retail%20Branch%20Server%204.0","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"SUSE:Manager Server 4.0","fixed":["5.44-3.8.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/suse/stunnel\u0026distro=SUSE%20Manager%20Server%204.0","source":"SUSE-SU-2021:1465-1"},{"ecosystem":"openSUSE:Leap 15.2","fixed":["5.57-lp152.2.6.1"],"introduced":["0"],"last_affected":[],"package":"stunnel","purl":"pkg:rpm/opensuse/stunnel\u0026distro=openSUSE%20Leap%2015.2","source":"openSUSE-SU-2021:0409-1"}],"prev":{"headline":"Incorrect Authorization in PostgreSQL","id":"CVE-2021-20229"},"products":["stunnel"],"published":"2021-02-23","related":[{"cvss_score":10,"headline":"Other in n/a","id":"CVE-2001-0060","kev_date_added":null,"published":"2001-05-07"},{"cvss_score":9.3,"headline":"Memory corruption in n/a","id":"CVE-2011-2940","kev_date_added":null,"published":"2011-08-25"},{"cvss_score":7.2,"headline":"Unspecified vulnerability in stunnel before 4.23, when running as a service on Windows, allows local users to gain privileges via unknown attack vectors.","id":"CVE-2008-2400","kev_date_added":null,"published":"2008-05-22"},{"cvss_score":6.8,"headline":"Security feature bypass in n/a","id":"CVE-2008-2420","kev_date_added":null,"published":"2008-05-23"},{"cvss_score":6.6,"headline":"Integer overflow in n/a","id":"CVE-2013-1762","kev_date_added":null,"published":"2013-03-08"},{"cvss_score":5.8,"headline":"Auth bypass in n/a","id":"CVE-2015-3644","kev_date_added":null,"published":"2015-05-14"}],"sources":[{"class":"attribution","licence":"MIT","name":"AlmaLinux","prefix":"ALSA"},{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"Red Hat","prefix":"RHSA"},{"class":"attribution","licence":"BSD","name":"Rocky Linux","prefix":"RLSA"},{"class":"attribution","licence":"CC BY 4.0","name":"SUSE","prefix":"SUSE"},{"class":"attribution","licence":"CC BY 4.0","name":"SUSE","prefix":"openSUSE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-03","vendors":["n/a"]},"summary":"Attackers with valid CA-signed certificates can bypass redirect restrictions to access tunneled services, compromising confidentiality.","url":"https://insights.sbomify.com/CVE-2021-20230/"}