{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-63073 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-63073 is a critical denial of service vulnerability in Openssl Openssl, published on 25 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-63073 and fix it if it is affected.\n\nWhat it is: CVE-2026-63073 is a critical denial of service vulnerability in Openssl Openssl, published on 25 Aug 2026. 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-2026-63073 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-2026-63073/ (Markdown: https://insights.sbomify.com/CVE-2026-63073/index.md)","id":"CVE-2026-63073","markdown":"https://insights.sbomify.com/CVE-2026-63073/index.md","name":"CVE-2026-63073","record":{"aliases":["ALPINE-CVE-2026-63073","AZL-97950","BELL-CVE-2026-63073","CLEANSTART-2026-UH94851","DEBIAN-CVE-2026-63073","GHSA-826x-qg76-xqjx","MINI-f4vr-f483-hr9j","UBUNTU-CVE-2026-63073"],"analysis":{"component_type":"library","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"OpenSSL library","requires_auth":"none","summary":"A malicious CMP endpoint can crash a client by sending a crafted sender DN that triggers a format string vulnerability in OpenSSL's response validation.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"openssl","cpe":[{"product":"openssl","vendor":"openssl"}],"cvss":{"score":9.8,"severity":"critical","source":"cisa-adp","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-134","name":"Use of Externally-Controlled Format String"}],"description":"Issue summary: OpenSSL CMP response validation passed an unexpected response\nsender distinguished name directly as the format string to `ERR_raise_data()`.\n\nImpact summary: A malicious or intercepted CMP endpoint can crash a CMP client\nthat enforces an expected sender or uses a pinned server certificate whose\nsubject becomes the default expected sender.\n\nCWE: CWE-134 (Use of Externally-Controlled Format String)\n\nDescription: When validating a received CMP message, ossl_cmp_msg_check_update()\nconverts the peer-supplied sender distinguished name with X509_NAME_oneline()\nand passes it directly as the format argument to ERR_raise_data(). Percent\ncharacters survive the conversion, so a sender DN such as \"CN=%s%n\" reaches\nBIO_vsnprintf() as an attacker-controlled format string with no matching variadic\narguments. This path is only reached when the caller configures an expected\nsender or pins a server certificate, which is the normal configuration for a\nCMP client validating server responses.\n\nSince the attacker controls the format string but none of the variadic\narguments, such specifiers as %s and %n dereference or write through unrelated\nstack contents and crash the client. The reliable consequence is a denial of\nservice, when the response comes from a malicious or intercepted CMP endpoint.\nThere is no controlled memory write, arbitrary-address read, or reliable path\nto remote code execution.\n\nFIPS impact: no\n\nNo FIPS modules are affected by this issue, as the CMP protocol\nimplementation is outside the OpenSSL FIPS module boundary.","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":"Untrusted Sender DN Used as Format String in CMP Response Validation","id":"CVE-2026-63073","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"openssl:openssl","products":["openssl:openssl"],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":5,"next":{"headline":"CMP Indefinite Cache Growth of ExtraCerts","id":"CVE-2026-63074"},"packages":[],"prev":{"headline":"Heap Buffer Overflow in CMS Key Unwrapping","id":"CVE-2026-63072"},"products":["OpenSSL"],"published":"2026-08-25","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":"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":"total"},"state":"PUBLISHED","updated":"2026-08-31","vendors":["OpenSSL"]},"summary":"A malicious CMP endpoint can crash a client by sending a crafted sender DN that triggers a format string vulnerability in OpenSSL's response validation.","url":"https://insights.sbomify.com/CVE-2026-63073/"}