{"id":"CVE-2026-58465","summary":"Eclipse Wakaama CoAP Block1 Handler Unbounded Memory Allocation DoS","details":"Eclipse Wakaama before snapshot/2026-05-26 contains an unbounded memory allocation vulnerability in the CoAP Block1 handler within coap/block.c that allows unauthenticated remote attackers to exhaust server memory by sending a sequence of Block1 PUT requests with incrementing block numbers. Attackers can target the registration endpoint over UDP without authentication, causing the server to repeatedly reallocate a growing accumulation buffer by appending each block payload without enforcing any maximum total size limit, resulting in denial of service through memory exhaustion.","modified":"2026-08-12T16:41:36.729096Z","published":"2026-07-02T17:55:12.038Z","database_specific":{"cna_assigner":"VulnCheck","cwe_ids":["CWE-770"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58465.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58465.json"},{"type":"ADVISORY","url":"https://github.com/eclipse-wakaama/wakaama/releases/tag/snapshots%2F2026-05-26"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-58465"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/eclipse-wakaama-coap-block1-handler-unbounded-memory-allocation-dos"},{"type":"REPORT","url":"https://github.com/eclipse-wakaama/wakaama/pull/881"},{"type":"FIX","url":"https://github.com/eclipse-wakaama/wakaama/commit/a83f1ca28fa090fbc03c3669fef40daf4f89cd03"},{"type":"PACKAGE","url":"https://github.com/eclipse-wakaama/wakaama"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/eclipse-wakaama/wakaama","events":[{"introduced":"0"},{"fixed":"a83f1ca28fa090fbc03c3669fef40daf4f89cd03"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"snapshot/2026-05-26"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["snapshots/2023-03-31","snapshots/2022-08-03","v1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-58465.json","vanir_signatures_modified":"2026-08-12T16:41:36Z","vanir_signatures":[{"deprecated":false,"digest":{"line_hashes":["254574986245705885662859023578170410883","155392224499935136968742554198138353894","268159411966634232766203272479565361860","236939823293802254555735352902235955941","136003925378428211672187817758103963686","36423602874163882900132844395046552873","59498748051464752253410391580504916921"],"threshold":0.9},"id":"CVE-2026-58465-2d561d96","signature_type":"Line","signature_version":"v1","source":"https://github.com/eclipse-wakaama/wakaama/commit/a83f1ca28fa090fbc03c3669fef40daf4f89cd03","target":{"file":"tests/coap_block1tests.c"}},{"id":"CVE-2026-58465-a0b40c5a","signature_type":"Function","signature_version":"v1","source":"https://github.com/eclipse-wakaama/wakaama/commit/a83f1ca28fa090fbc03c3669fef40daf4f89cd03","target":{"file":"coap/block.c","function":"prv_coap_block_handler"},"deprecated":false,"digest":{"function_hash":"248155539965842206699278287991987471196","length":1494}},{"deprecated":false,"digest":{"line_hashes":["40634180268366884496138022984649067380","212405834832827732985586244637627649933","230231201715750187825274237849696519263","293305728399603890987630647751350716057","174649095191718470396214942515235351382","192257635115597055900902778847850343544","234375329169740172336585081790780506921","114667304822017033816334418361744942761","337447643777904453855818732707196117823","4059139140162262212724154641559360268"],"threshold":0.9},"id":"CVE-2026-58465-eaa84f1d","signature_type":"Line","signature_version":"v1","source":"https://github.com/eclipse-wakaama/wakaama/commit/a83f1ca28fa090fbc03c3669fef40daf4f89cd03","target":{"file":"coap/block.c"}}]}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}