{"id":"CVE-2026-83376","kind":"vulnerability","aliases":["CVE-2026-83376"],"related":[],"title":"Oracle Java SE: JSSE flaw lets network attacker alter some data","description":"Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: JSSE).  Supported versions that are affected are Oracle Java SE: 8u503, 8u503-perf, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27; Oracle GraalVM for JDK: 17.0.20.1 and  21.0.12.1; Oracle GraalVM Enterprise Edition: 21.3.19.1.1. Difficult to exploit vulnerability allows unauthenticated attacker with network access via TLS to compromise Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition.  Successful attacks of this vulnerability can result in  unauthorized update, insert or delete access to some of Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition accessible data. Note: This vulnerability can be exploited by using APIs in the specified Component, e.g., through a web service which supplies data to the APIs. This vulnerability also applies to Java deployments, typically in clients running sandboxed Java Web Start applications or sandboxed Java applets, that load and run untrusted code (e.g., code that comes from the internet) and rely on the Java sandbox for security. CVSS 3.1 Base Score 3.7 (Integrity impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N).","summary":"A flaw in the JSSE (Java Secure Socket Extension) component of Oracle Java SE and GraalVM lets an unauthenticated attacker over TLS make unauthorized changes to some accessible data. The sources rate it low (CVSS 3.7, integrity impact only) and say exploitation is difficult.","severity":"low","cvss":3.7,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["graalvm","java","jdk","runtime","self-hosted","tls"],"not_affected_if":["no-java-services","unaffected-version"],"how_to_check":"- Run `java -version` and compare the output against the affected versions: 8u503, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27 (Oracle Java SE) and 17.0.20.1, 21.0.12.1 (GraalVM for JDK), 21.3.19.1.1 (GraalVM Enterprise).\n- Check whether any service exposes JSSE-backed APIs to untrusted network clients or runs sandboxed Java Web Start or applets.","fix":"- Upgrade Oracle Java SE to a patched release per Oracle's July 2026 Critical Patch Update advisory (exact fixed versions unknown from the sources).\n- Upgrade GraalVM for JDK and GraalVM Enterprise Edition to patched builds (fixed versions unknown from the sources).","status":"open","published_at":"2026-10-20T22:19:53+00:00","first_seen_at":"2026-10-23T21:57:25+00:00","triaged_at":"2026-10-25T04:43:56+00:00","updated_at":"2026-10-25T04:43:56+00:00","category":"runtime","confidence":0.6,"triage":{"at":"2026-10-25T04:43:56Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade Oracle Java SE to a patched release per Oracle's July 2026 Critical Patch Update advisory (exact fixed versions unknown from the sources).\n- Upgrade GraalVM for JDK and GraalVM Enterprise Edition to patched builds (fixed versions unknown from the sources).","reach":"internet","title":"Oracle Java SE: JSSE flaw lets network attacker alter some data","impact":"low","summary":"A flaw in the JSSE (Java Secure Socket Extension) component of Oracle Java SE and GraalVM lets an unauthenticated attacker over TLS make unauthorized changes to some accessible data. The sources rate it low (CVSS 3.7, integrity impact only) and say exploitation is difficult.","category":"runtime","nicknames":[],"who_cares":["java","jdk","graalvm","tls","self-hosted"],"confidence":0.6,"needs_auth":"no","worst_case":"Attacker alters some data the Java application can access.","analyst_note":"Confirm fixed versions and exact exploit conditions from Oracle's July 2026 CPU advisory; the NVD entry gives no fix versions.","how_to_check":"- Run `java -version` and compare the output against the affected versions: 8u503, 11.0.32.1, 17.0.20.1, 21.0.12.1, 25.0.4.1, 27 (Oracle Java SE) and 17.0.20.1, 21.0.12.1 (GraalVM for JDK), 21.3.19.1.1 (GraalVM Enterprise).\n- Check whether any service exposes JSSE-backed APIs to untrusted network clients or runs sandboxed Java Web Start or applets.","needs_analyst":true,"not_affected_if":["unaffected-version","no-java-services"],"who_is_affected":"Systems running the listed Oracle Java SE, GraalVM for JDK or GraalVM Enterprise versions where a network service passes untrusted input to JSSE APIs over TLS, or where Java applets or Web Start apps run untrusted code. Teams that run only unaffected versions or no Java workloads can skip it.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"low"},"cost_usd":0.000767,"input_tokens":3799,"output_tokens":775,"severity_before":"low"},"analyst_status":null,"analyst_note":null,"search":"'-2026':13A,16A '-83376':14A,17A '/av':252C '11.0.32.1':104C '17.0.20.1':105C,113C '21.0.12.1':106C,115C '21.3.19.1.1':120C '25.0.4.1':107C '27':108C '3.1':242C,251C '3.7':61B,245C '8u503':100C,102C '8u503-perf':101C 'access':53B,130C,159C,174C 'affect':95C 'allow':125C 'also':202C 'alter':9A 'api':184C,199C 'applet':219C 'appli':203C 'applic':215C 'attack':8A,45B,127C,147C 'base':243C 'chang':50B 'client':209C 'code':225C,227C 'come':229C 'compon':35B,89C,188C 'compromis':134C 'cve':12A,15A 'cvss':60B,241C,248C,250C 'data':11A,54B,175C,196C 'delet':158C 'deploy':206C 'difficult':69B,121C 'e.g':189C,226C 'edit':83C,119C,145C,173C 'enterpris':82C,118C,144C,172C 'exploit':67B,123C,181C 'extens':34B 'flaw':5A,27B 'graalvm':18B,41B,77C,81C,110C,117C,139C,143C,167C,171C 'h/pr':254C 'host':24B 'impact':63B,247C 'insert':156C 'integr':62B,246C 'internet':232C 'java':2A,19B,31B,38B,74C,87C,98C,136C,164C,205C,212C,218C,237C 'jdk':20B,79C,112C,141C,169C 'jsse':4A,30B,90C 'l/a':259C 'let':6A,42B 'load':221C 'low':59B 'make':48B 'n':260C 'n/ac':253C 'n/i':258C 'n/s':256C 'n/ui':255C 'network':7A,129C 'note':176C 'oracl':1A,37B,73C,76C,80C,86C,97C,109C,116C,135C,138C,142C,163C,166C,170C 'perf':103C 'product':84C 'rate':57B 'reli':234C 'result':152C 'run':210C,223C 'runtim':21B 'sandbox':211C,217C,238C 'say':66B 'score':244C 'se':3A,39B,75C,88C,99C,137C,165C 'secur':32B,240C 'self':23B 'self-host':22B 'servic':193C 'socket':33B 'sourc':56B 'specifi':187C 'start':214C 'success':146C 'suppli':195C 'support':91C 'tls':25B,47B,132C 'typic':207C 'u/c':257C 'unauthent':44B,126C 'unauthor':49B,154C 'untrust':224C 'updat':155C 'use':183C 'vector':249C 'version':92C 'via':131C 'vulner':70C,124C,150C,178C,201C 'web':192C,213C","nicknames":[],"mitigations":[],"who_affected":"Systems running the listed Oracle Java SE, GraalVM for JDK or GraalVM Enterprise versions where a network service passes untrusted input to JSSE APIs over TLS, or where Java applets or Web Start apps run untrusted code. Teams that run only unaffected versions or no Java workloads can skip it.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-20T22:19:53+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","cvss_by":"secalert_us@oracle.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-83376","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-83376","severity":null,"published_at":"2026-10-20T22:19:53+00:00","modified_at":"2026-10-21T18:44:19+00:00","first_seen_at":"2026-10-23T21:57:25+00:00","fetched_at":"2026-10-23T22:29:00+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"}