{"id":"CVE-2026-101730","kind":"vulnerability","aliases":["CVE-2026-101730"],"related":[],"title":"MySQL Server optimizer flaw lets a privileged user crash the database","description":"Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Optimizer).  Supported versions that are affected are MySQL Server: 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1; MySQL Cluster: 8.0.0-8.0.49, 8.4.0-8.4.12, 9.7.0-9.7.3 and  26.7.0-26.7.1. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server, MySQL Cluster.  Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server, MySQL Cluster. CVSS 3.1 Base Score 4.9 (Availability impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).","summary":"A flaw in the MySQL Server optimizer lets a highly privileged account on the network hang or repeatedly crash MySQL Server and MySQL Cluster. The attacker gets denial of service, not data access or code execution, according to the CVSS vector.","severity":"medium","cvss":4.9,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["databases","mysql","package","self-hosted"],"not_affected_if":["auth-required","default-config"],"how_to_check":"- Run `SELECT VERSION();` against the server and compare with the affected ranges: MySQL Server 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1; MySQL Cluster 8.0.0-8.0.49, 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1.\n- Check for MySQL Cluster deployments, since they carry a wider affected range.","fix":"- Upgrade MySQL Server and MySQL Cluster to a release outside the affected ranges; the sources do not name the fixed version, so check Oracle's MySQL security advisory.","status":"open","published_at":"2026-10-20T22:18:27+00:00","first_seen_at":"2026-10-23T21:57:23+00:00","triaged_at":"2026-10-25T04:31:26+00:00","updated_at":"2026-10-25T04:31:26+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-10-25T04:31:26Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade MySQL Server and MySQL Cluster to a release outside the affected ranges; the sources do not name the fixed version, so check Oracle's MySQL security advisory.","reach":"network","title":"MySQL Server optimizer flaw lets a privileged user crash the database","impact":"low","summary":"A flaw in the MySQL Server optimizer lets a highly privileged account on the network hang or repeatedly crash MySQL Server and MySQL Cluster. The attacker gets denial of service, not data access or code execution, according to the CVSS vector.","category":"package","nicknames":[],"who_cares":["mysql","databases","self-hosted"],"confidence":0.7,"needs_auth":"yes","worst_case":"Database server hangs or repeatedly crashes, causing denial of service.","analyst_note":"Confirm the fixed MySQL version for each branch in Oracle's MySQL security advisory for the 2026 CPU; the sources do not give it.","how_to_check":"- Run `SELECT VERSION();` against the server and compare with the affected ranges: MySQL Server 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1; MySQL Cluster 8.0.0-8.0.49, 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1.\n- Check for MySQL Cluster deployments, since they carry a wider affected range.","needs_analyst":true,"not_affected_if":["default-config","auth-required"],"who_is_affected":"Systems running MySQL Server or MySQL Cluster in the listed version ranges. The attacker needs high privileges and network access, so exposure is mainly where many accounts hold broad database rights or the server is reachable from untrusted networks. Servers on versions outside the listed ranges can skip it.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000697,"input_tokens":3585,"output_tokens":677,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-101730':14A,17A '-2026':13A,16A '/av':159C '26.7.0':91C,102C '26.7.1':92C,103C '3.1':149C,158C '4.9':152C '8.0.0':95C '8.0.49':96C '8.4.0':87C,97C '8.4.12':88C,98C '9.7.0':89C,99C '9.7.3':90C,100C 'abil':132C 'access':56B,113C 'accord':60B 'account':35B 'affect':83C 'allow':107C 'attack':49B,110C,124C 'avail':153C 'base':150C 'caus':134C 'cluster':47B,71C,94C,122C,147C 'code':58B 'complet':141C 'compon':76C 'compromis':118C 'crash':9A,42B,140C 'cve':12A,15A 'cvss':63B,148C,155C,157C 'data':55B 'databas':11A,18B 'denial':51B 'dos':142C 'easili':104C 'execut':59B 'exploit':105C 'flaw':4A,25B 'frequent':138C 'get':50B 'h':167C 'h/ui':162C 'hang':39B,136C 'high':33B,108C 'host':23B 'impact':154C 'l/pr':161C 'let':5A,31B 'multipl':115C 'mysql':1A,19B,28B,43B,46B,68C,70C,75C,85C,93C,119C,121C,144C,146C 'n/a':166C 'n/ac':160C 'n/i':165C 'n/s':163C 'network':38B,112C 'optim':3A,30B,78C 'oracl':74C 'packag':20B 'privileg':7A,34B,109C 'product':72C 'protocol':116C 'repeat':41B,139C 'result':129C 'score':151C 'self':22B 'self-host':21B 'server':2A,29B,44B,69C,77C,86C,120C,145C 'servic':53B 'success':123C 'support':79C 'u/c':164C 'unauthor':131C 'user':8A 'vector':64B,156C 'version':80C 'via':114C 'vulner':65C,106C,127C","nicknames":[],"mitigations":[],"who_affected":"Systems running MySQL Server or MySQL Cluster in the listed version ranges. The attacker needs high privileges and network access, so exposure is mainly where many accounts hold broad database rights or the server is reachable from untrusted networks. Servers on versions outside the listed ranges can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-20T22:18:27+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H","cvss_by":"secalert_us@oracle.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-101730","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-101730","severity":null,"published_at":"2026-10-20T22:18:27+00:00","modified_at":"2026-10-22T18:17:17+00:00","first_seen_at":"2026-10-23T21:57:23+00:00","fetched_at":"2026-10-23T22:28:59+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}