{"answers":{"affected":"2 open source packages ship an affected version, including io.netty:netty-handler. It affects 1 product.","exploited":"There is no known exploitation of CVE-2023-34462 in the wild and no public exploit code.","fix":"Upgrade io.netty:netty-handler to 4.1.94.Final or later.","what":"CVE-2023-34462 is a medium-severity denial of service vulnerability in Netty Netty, published on 22 Jun 2023. Any signed-in user can exploit it over the network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2023-34462 and fix it if it is affected.\n\nWhat it is: CVE-2023-34462 is a medium-severity denial of service vulnerability in Netty Netty, published on 22 Jun 2023. Any signed-in user can exploit it over the network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2023-34462 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- io.netty:netty-handler (Maven): affected all versions; fixed in 4.1.94.Final\n- io.netty:netty-handler (Maven): affected all versions; fixed in 4.1.94.Final\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-2023-34462/ (Markdown: https://insights.sbomify.com/CVE-2023-34462/index.md)","id":"CVE-2023-34462","markdown":"https://insights.sbomify.com/CVE-2023-34462/index.md","name":"CVE-2023-34462","record":{"aliases":["CLEANSTART-2026-IQ25144","CLEANSTART-2026-JJ44639","CLEANSTART-2026-SO54386","CLSA-2026-1776818207","DEBIAN-CVE-2023-34462","ECHO-271e-3fbf-886d","GHSA-6mjq-h674-j845","MINI-c427-29rw-3hmj","MINI-fjr5-4gwv-qqhw","MINI-v3g6-99q9-f459","SUSE-SU-2023:2974-1","UBUNTU-CVE-2023-34462"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Netty network framework","requires_auth":"low_privilege","summary":"Attackers can cause excessive memory allocation in Netty's SniHandler during TLS handshakes, leading to denial of service.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"netty","vendor":"netty"}],"cvss":{"score":6.5,"severity":"medium","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-770","name":"Allocation of Resources Without Limits or Throttling"},{"id":"CWE-400","name":"Uncontrolled Resource Consumption"}],"description":"Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers \u0026 clients. The `SniHandler` can allocate up to 16MB of heap for each channel during the TLS handshake. When the handler or the channel does not have an idle timeout, it can be used to make a TCP server using the `SniHandler` to allocate 16MB of heap. The `SniHandler` class is a handler that waits for the TLS handshake to configure a `SslHandler` according to the indicated server name by the `ClientHello` record. For this matter it allocates a `ByteBuf` using the value defined in the `ClientHello` record. Normally the value of the packet should be smaller than the handshake packet but there are not checks done here and the way the code is written, it is possible to craft a packet that makes the `SslClientHelloHandler`. This vulnerability has been fixed in version 4.1.94.Final.","ecosystems":["Maven","SUSE:Linux Enterprise Module for Development Tools 15 SP4","SUSE:Linux Enterprise Module for Development Tools 15 SP5","SUSE:Linux Enterprise Module for Package Hub 15 SP5","SUSE:Linux Enterprise Real Time 15 SP3","openSUSE:Leap 15.4","openSUSE:Leap 15.5"],"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":"netty-handler SniHandler 16MB allocation","id":"CVE-2023-34462","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"Maven","product":"netty:netty","products":["netty:netty"],"type":"denial_of_service","year":"2023"},"n_packages":10,"n_references":5,"next":{"headline":"Unauthorized users can delete applications in DataEase","id":"CVE-2023-34463"},"packages":[{"ecosystem":"Maven","fixed":["4.1.94.Final"],"introduced":["0"],"last_affected":[],"package":"io.netty:netty-handler","purl":null,"source":"GHSA-6mjq-h674-j845"},{"ecosystem":"Maven","fixed":["4.1.94.Final"],"introduced":["0"],"last_affected":[],"package":"io.netty:netty-handler","purl":"pkg:maven/io.netty/netty-handler","source":"GHSA-6mjq-h674-j845"},{"ecosystem":"SUSE:Linux Enterprise Module for Development Tools 15 SP4","fixed":["2.0.61-150200.3.13.1"],"introduced":["0"],"last_affected":[],"package":"netty-tcnative","purl":"pkg:rpm/suse/netty-tcnative\u0026distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP4","source":"SUSE-SU-2023:2974-1"},{"ecosystem":"SUSE:Linux Enterprise Module for Development Tools 15 SP5","fixed":["2.0.61-150200.3.13.1"],"introduced":["0"],"last_affected":[],"package":"netty-tcnative","purl":"pkg:rpm/suse/netty-tcnative\u0026distro=SUSE%20Linux%20Enterprise%20Module%20for%20Development%20Tools%2015%20SP5","source":"SUSE-SU-2023:2974-1"},{"ecosystem":"SUSE:Linux Enterprise Module for Package Hub 15 SP5","fixed":["4.1.94-150200.4.17.1"],"introduced":["0"],"last_affected":[],"package":"netty","purl":"pkg:rpm/suse/netty\u0026distro=SUSE%20Linux%20Enterprise%20Module%20for%20Package%20Hub%2015%20SP5","source":"SUSE-SU-2023:2974-1"},{"ecosystem":"SUSE:Linux Enterprise Real Time 15 SP3","fixed":["2.0.61-150200.3.13.1"],"introduced":["0"],"last_affected":[],"package":"netty-tcnative","purl":"pkg:rpm/suse/netty-tcnative\u0026distro=SUSE%20Linux%20Enterprise%20Real%20Time%2015%20SP3","source":"SUSE-SU-2023:2974-1"},{"ecosystem":"openSUSE:Leap 15.4","fixed":["4.1.94-150200.4.17.1"],"introduced":["0"],"last_affected":[],"package":"netty","purl":"pkg:rpm/opensuse/netty\u0026distro=openSUSE%20Leap%2015.4","source":"SUSE-SU-2023:2974-1"},{"ecosystem":"openSUSE:Leap 15.4","fixed":["2.0.61-150200.3.13.1"],"introduced":["0"],"last_affected":[],"package":"netty-tcnative","purl":"pkg:rpm/opensuse/netty-tcnative\u0026distro=openSUSE%20Leap%2015.4","source":"SUSE-SU-2023:2974-1"},{"ecosystem":"openSUSE:Leap 15.5","fixed":["4.1.94-150200.4.17.1"],"introduced":["0"],"last_affected":[],"package":"netty","purl":"pkg:rpm/opensuse/netty\u0026distro=openSUSE%20Leap%2015.5","source":"SUSE-SU-2023:2974-1"},{"ecosystem":"openSUSE:Leap 15.5","fixed":["2.0.61-150200.3.13.1"],"introduced":["0"],"last_affected":[],"package":"netty-tcnative","purl":"pkg:rpm/opensuse/netty-tcnative\u0026distro=openSUSE%20Leap%2015.5","source":"SUSE-SU-2023:2974-1"}],"prev":{"headline":"Cross-site Scripting (XSS) Availability in PyBB","id":"CVE-2023-34461"},"products":["netty"],"published":"2023-06-22","related":[{"cvss_score":9.1,"headline":"Netty: SNI Routing Bypass via Fragmented TLS ClientHello Causing Fallback to Default SslContext","id":"CVE-2026-75595","kev_date_added":null,"published":"2026-08-19"},{"cvss_score":8.7,"headline":"Netty: Fragmented ClientHello records trigger quadratic pre-handshake reassembly in default SNI parsing","id":"CVE-2026-75596","kev_date_added":null,"published":"2026-08-19"},{"cvss_score":8.7,"headline":"Netty Bzip2Decoder: Infinite Loop in RLE State Machine Leads to Event-Loop Thread Hang","id":"CVE-2026-59901","kev_date_added":null,"published":"2026-07-29"},{"cvss_score":8.7,"headline":"Netty codec-haproxy: Signed-Byte Sentinel Collision in HAProxyMessageDecoder Leads to Unbounded Memory Exhaustion","id":"CVE-2026-55851","kev_date_added":null,"published":"2026-07-21"},{"cvss_score":8.7,"headline":"Netty SpdyHttpDecoder: ByteBuf Reference Leak on RST_STREAM Leads to Native Memory Exhaustion","id":"CVE-2026-56745","kev_date_added":null,"published":"2026-07-21"},{"cvss_score":8.7,"headline":"Netty Vulnerable to DNS Cache Poisoning via Missing Bailiwick Checks in CNAME Records","id":"CVE-2026-45674","kev_date_added":null,"published":"2026-06-12"},{"cvss_score":8.7,"headline":"Netty has Insufficient Bailiwick Validation for NS Records","id":"CVE-2026-47691","kev_date_added":null,"published":"2026-06-12"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"SUSE","prefix":"SUSE"},{"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":"partial"},"state":"PUBLISHED","updated":"2025-02-13","vendors":["netty"]},"summary":"Attackers can cause excessive memory allocation in Netty's SniHandler during TLS handshakes, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2023-34462/"}