{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2026-2673 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-2673 is a medium-severity vulnerability in Openssl Openssl, published on 13 Mar 2026."},"fix_prompt":"Check this codebase for CVE-2026-2673 and fix it if it is affected.\n\nWhat it is: CVE-2026-2673 is a medium-severity vulnerability in Openssl Openssl, published on 13 Mar 2026. \nExploitation: There is no known exploitation of CVE-2026-2673 in the wild and no public exploit code.\n\nAffected product: Openssl Openssl. 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-2026-2673/ (Markdown: https://insights.sbomify.com/CVE-2026-2673/index.md)","id":"CVE-2026-2673","markdown":"https://insights.sbomify.com/CVE-2026-2673/index.md","name":"CVE-2026-2673","record":{"aliases":["ALPINE-CVE-2026-2673","BELL-CVE-2026-2673","DEBIAN-CVE-2026-2673","GHSA-wj64-gh9j-xm82","JLSEC-2026-271","MINI-m8jj-632g-59cq","UBUNTU-CVE-2026-2673"],"analysis":null,"analysis_generated_by":null,"assigner":"openssl","cpe":[{"product":"openssl","vendor":"openssl"},{"product":"simatic_cn_4100_firmware","vendor":"siemens"}],"cvss":{"score":6.5,"severity":"medium","source":"cisa-adp","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L","version":"3.1"},"cwes":[{"id":"CWE-757","name":"Selection of Less-Secure Algorithm During Negotiation"}],"description":"Issue summary: An OpenSSL TLS 1.3 server may fail to negotiate the expected\npreferred key exchange group when its key exchange group configuration includes\nthe default by using the 'DEFAULT' keyword.\n\nImpact summary: A less preferred key exchange may be used even when a more\npreferred group is supported by both client and server, if the group\nwas not included among the client's initial predicated keyshares.\nThis will sometimes be the case with the new hybrid post-quantum groups,\nif the client chooses to defer their use until specifically requested by\nthe server.\n\nIf an OpenSSL TLS 1.3 server's configuration uses the 'DEFAULT' keyword to\ninterpolate the built-in default group list into its own configuration, perhaps\nadding or removing specific elements, then an implementation defect causes the\n'DEFAULT' list to lose its 'tuple' structure, and all server-supported groups\nwere treated as a single sufficiently secure 'tuple', with the server not\nsending a Hello Retry Request (HRR) even when a group in a more preferred tuple\nwas mutually supported.\n\nAs a result, the client and server might fail to negotiate a mutually supported\npost-quantum key agreement group, such as 'X25519MLKEM768', if the client's\nconfiguration results in only 'classical' groups (such as 'X25519' being the\nonly ones in the client's initial keyshare prediction).\n\nOpenSSL 3.5 and later support a new syntax for selecting the most preferred TLS\n1.3 key agreement group on TLS servers.  The old syntax had a single 'flat'\nlist of groups, and treated all the supported groups as sufficiently secure.\nIf any of the keyshares predicted by the client were supported by the server\nthe most preferred among these was selected, even if other groups supported by\nthe client, but not included in the list of predicted keyshares would have been\nmore preferred, if included.\n\nThe new syntax partitions the groups into distinct 'tuples' of roughly\nequivalent security.  Within each tuple the most preferred group included among\nthe client's predicted keyshares is chosen, but if the client supports a group\nfrom a more preferred tuple, but did not predict any corresponding keyshares,\nthe server will ask the client to retry the ClientHello (by issuing a Hello\nRetry Request or HRR) with the most preferred mutually supported group.\n\nThe above works as expected when the server's configuration uses the built-in\ndefault group list, or explicitly defines its own list by directly defining the\nvarious desired groups and group 'tuples'.\n\nNo OpenSSL FIPS modules are affected by this issue, the code in question lies\noutside the FIPS boundary.\n\nOpenSSL 3.6 and 3.5 are vulnerable to this issue.\n\nOpenSSL 3.6 users should upgrade to OpenSSL 3.6.2 once it is released.\nOpenSSL 3.5 users should upgrade to OpenSSL 3.5.6 once it is released.\n\nOpenSSL 3.4, 3.3, 3.0, 1.0.2 and 1.1.1 are not affected by this issue.","ecosystems":[],"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":"OpenSSL TLS 1.3 server may choose unexpected key agreement group","id":"CVE-2026-2673","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"openssl:openssl","products":["openssl:openssl"],"type":null,"year":"2026"},"n_packages":0,"n_references":3,"next":{"headline":"Memory corruption in Connext Professional","id":"CVE-2026-2674"},"packages":[],"prev":{"headline":"Tsinghua Unigroup Electronic Archives System downLoad download path traversal","id":"CVE-2026-2672"},"products":["OpenSSL"],"published":"2026-03-13","related":[{"cvss_score":10,"headline":"Null dereference in n/a","id":"CVE-2009-3245","kev_date_added":null,"published":"2010-03-05"},{"cvss_score":10,"headline":"Memory corruption in n/a","id":"CVE-2006-3738","kev_date_added":null,"published":"2006-09-28"},{"cvss_score":9.8,"headline":"Untrusted Sender DN Used as Format String in CMP Response Validation","id":"CVE-2026-63073","kev_date_added":null,"published":"2026-08-25"},{"cvss_score":9.8,"headline":"Use after free in n/a","id":"CVE-2016-6309","kev_date_added":null,"published":"2016-09-26"},{"cvss_score":9.8,"headline":"Integer overflow in n/a","id":"CVE-2016-0799","kev_date_added":null,"published":"2016-03-03"},{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2016-2842","kev_date_added":null,"published":"2016-03-03"},{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2003-0545","kev_date_added":null,"published":"2003-10-01"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"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":"yes","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-05-18","vendors":["OpenSSL"]},"summary":null,"url":"https://insights.sbomify.com/CVE-2026-2673/"}