{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2026-55953 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2026-55953 is a critical vulnerability in Erlang OTP, published on 27 Jul 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-2026-55953 and fix it if it is affected.\n\nWhat it is: CVE-2026-55953 is a critical vulnerability in Erlang OTP, published on 27 Jul 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-2026-55953 in the wild and no public exploit code.\n\nAffected product: Erlang OTP. 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-2026-55953/ (Markdown: https://insights.sbomify.com/CVE-2026-55953/index.md)","id":"CVE-2026-55953","markdown":"https://insights.sbomify.com/CVE-2026-55953/index.md","name":"CVE-2026-55953","record":{"aliases":["AZL-94196","DEBIAN-CVE-2026-55953","EEF-CVE-2026-55953","GHSA-c6cw-pr89-w882","UBUNTU-CVE-2026-55953"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["data_read","data_modify"],"network_reachable":"yes","non_default_config":false,"product_category":"Erlang OTP SSL library","requires_auth":"none","summary":"An on-path attacker can bypass server authentication in Erlang OTP TLS clients by forcing anonymous cipher suites, enabling man-in-the-middle attacks.","user_interaction":"not_required","vuln_class":"security_feature_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"EEF","cpe":[{"product":"erlang\\/otp","vendor":"erlang"},{"product":"erlang\\/ssl","vendor":"erlang"}],"cvss":{"score":9.1,"severity":"critical","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-757","name":"Selection of Less-Secure Algorithm During Negotiation"}],"description":"The Erlang/OTP ssl TLS 1.2 (and earlier) and DTLS client does not verify that the cipher suite selected by the server in ServerHello was among the suites offered by the client in ClientHello. The client-side tls_handshake:hello/5 handler validates the negotiated protocol version and the downgrade sentinel but hands the server-chosen suite directly to ssl_handshake:handle_server_hello_extensions/9, which installs it without a membership check. The TLS 1.3 client path performs this check (per RFC 8446), so it is not affected.\n\nAn on-path attacker between the client and the intended server can respond with a ServerHello selecting an anonymous key exchange suite such as TLS_DH_anon_* or TLS_ECDH_anon_* that the client never offered. Anonymous suites do not require the server to present a certificate, so the entire verify_peer and cacerts configuration is bypassed: the attacker completes the handshake with its own ephemeral parameters, no certificate is validated, no hostname is checked, and ssl:connect returns {ok, Socket}. All subsequent application traffic is readable and modifiable by the attacker.\n\nThis issue affects OTP from OTP 17.0 before OTP 27.3.4.15, from OTP 28.0 before OTP 28.5.0.4, and from OTP 29.0 before OTP 29.0.4, corresponding to ssl from 5.3.4 before 11.2.12.11, from 11.3 before 11.6.0.4, and from 11.7 before 11.7.4. Whether OTP before OTP 17.0, corresponding to ssl before 5.3.4, is affected is unknown.","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":"TLS 1.2 and DTLS client accepts unoffered anonymous cipher suite, bypassing server authentication","id":"CVE-2026-55953","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"security_feature_bypass","year":"2026"},"n_packages":0,"n_references":7,"next":{"headline":"Missing ID token claim validation in ueberauth_apple allows account takeover","id":"CVE-2026-55954"},"packages":[],"prev":{"headline":"TLS 1.3 server denial of service via malformed ClientHello pre-shared key extension","id":"CVE-2026-55952"},"products":["OTP"],"published":"2026-07-27","related":[{"cvss_score":9.8,"headline":"Auth bypass in n/a","id":"CVE-2022-37026","kev_date_added":null,"published":"2022-09-21"},{"cvss_score":9.8,"headline":"Memory corruption in n/a","id":"CVE-2016-10253","kev_date_added":null,"published":"2017-03-18"},{"cvss_score":8.8,"headline":"Stack buffer overflow in SCTP error cause parsing in inet_drv allows remote VM crash","id":"CVE-2026-49759","kev_date_added":null,"published":"2026-06-10"},{"cvss_score":8.7,"headline":"TLS/DTLS denial of service via unbounded recursion on cross-signed peer certificate chain","id":"CVE-2026-58227","kev_date_added":null,"published":"2026-07-27"},{"cvss_score":8.7,"headline":"Denial of service via exponential certificate policy tree growth in path validation","id":"CVE-2026-59251","kev_date_added":null,"published":"2026-07-27"},{"cvss_score":8.7,"headline":"DTLS listener crash via race condition in dtls_packet_demux causes denial of service for all sessions","id":"CVE-2026-55950","kev_date_added":null,"published":"2026-07-02"}],"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":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-09-08","vendors":["Erlang"]},"summary":"An on-path attacker can bypass server authentication in Erlang OTP TLS clients by forcing anonymous cipher suites, enabling man-in-the-middle attacks.","url":"https://insights.sbomify.com/CVE-2026-55953/"}