{"id":"CVE-2026-87294","kind":"vulnerability","aliases":["CVE-2026-87294"],"related":[],"title":"Oracle Java SE: network attacker can read and change some data","description":"Vulnerability in the Oracle Java SE, Oracle GraalVM for JDK, Oracle GraalVM Enterprise Edition product of Oracle Java SE (component: Security).  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. Easily exploitable vulnerability allows unauthenticated attacker with network access via multiple protocols 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 as well as  unauthorized read access to a subset 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 6.5 (Confidentiality and Integrity impacts).  CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N).","summary":"A flaw in the Security component of Oracle Java SE and GraalVM lets an unauthenticated attacker over the network modify and read a subset of accessible data. The description notes it can be reached through APIs fed by a web service and also affects sandboxed Java Web Start and applet deployments.","severity":"medium","cvss":6.5,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["graalvm","java","java-web-services","jdk","runtime","self-hosted"],"not_affected_if":["no-network-exposed-java","patched-jdk"],"how_to_check":"- Run `java -version` and compare the output against the affected builds listed in the Oracle advisory (for example `8u503`, `11.0.32.1`, `17.0.20.1`, `21.0.12.1`, `25.0.4.1`).\n- For GraalVM, run `native-image --version` or `java -version` and check for `17.0.20.1`, `21.0.12.1` or `21.3.19.1.1`.","fix":"- Update Oracle Java SE to a patched release from the Oracle Critical Patch Update that fixes CVE-2026-87294; the exact fixed builds are unknown from these sources.\n- Update Oracle GraalVM for JDK and GraalVM Enterprise Edition to the patched release named in the Oracle advisory; unknown from these sources.","status":"open","published_at":"2026-10-20T22:20:06+00:00","first_seen_at":"2026-10-23T21:57:25+00:00","triaged_at":"2026-10-25T03:51:30+00:00","updated_at":"2026-10-25T03:51:30+00:00","category":"runtime","confidence":0.6,"triage":{"at":"2026-10-25T03:51:30Z","model":"claude-haiku-5-5","output":{"fix":"- Update Oracle Java SE to a patched release from the Oracle Critical Patch Update that fixes CVE-2026-87294; the exact fixed builds are unknown from these sources.\n- Update Oracle GraalVM for JDK and GraalVM Enterprise Edition to the patched release named in the Oracle advisory; unknown from these sources.","reach":"internet","title":"Oracle Java SE: network attacker can read and change some data","impact":"medium","summary":"A flaw in the Security component of Oracle Java SE and GraalVM lets an unauthenticated attacker over the network modify and read a subset of accessible data. The description notes it can be reached through APIs fed by a web service and also affects sandboxed Java Web Start and applet deployments.","category":"runtime","nicknames":[],"who_cares":["java","jdk","graalvm","self-hosted","java-web-services"],"confidence":0.6,"needs_auth":"no","worst_case":"Attacker reads and modifies some data in the Java runtime","analyst_note":"Confirm the patched Oracle Java SE, GraalVM for JDK and GraalVM Enterprise builds from the Oracle Critical Patch Update advisory and the NVD entry at https://nvd.nist.gov/vuln/detail/CVE-2026-87294.","how_to_check":"- Run `java -version` and compare the output against the affected builds listed in the Oracle advisory (for example `8u503`, `11.0.32.1`, `17.0.20.1`, `21.0.12.1`, `25.0.4.1`).\n- For GraalVM, run `native-image --version` or `java -version` and check for `17.0.20.1`, `21.0.12.1` or `21.3.19.1.1`.","needs_analyst":true,"not_affected_if":["patched-jdk","no-network-exposed-java"],"who_is_affected":"Any system running an affected Oracle Java SE or GraalVM build that exposes Java code reachable from the network, such as web services that pass input to the vulnerable Security APIs. Client deployments running untrusted code in sandboxed Web Start or applets are also in scope. Systems on patched builds, or with no network-facing Java code, can deprioritise this.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000783,"input_tokens":3869,"output_tokens":793,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-2026':13A,16A '-87294':14A,17A '/av':287C '11.0.32.1':114C '17.0.20.1':115C,123C '21.0.12.1':116C,125C '21.3.19.1.1':130C '25.0.4.1':117C '27':118C '3.1':275C,286C '6.5':278C '8u503':110C,112C '8u503-perf':111C 'access':54B,139C,169C,184C,191C,207C 'affect':72B,105C 'allow':134C 'also':71B,235C 'api':64B,217C,232C 'applet':78B,252C 'appli':236C 'applic':248C 'attack':5A,44B,136C,157C 'base':276C 'chang':9A 'client':242C 'code':258C,260C 'come':262C 'compon':34B,99C,221C 'compromis':144C 'confidenti':279C 'cve':12A,15A 'cvss':274C,283C,285C 'data':11A,55B,185C,208C,229C 'delet':168C 'deploy':79B,239C 'descript':57B 'e.g':222C,259C 'easili':131C 'edit':93C,129C,155C,183C,206C 'enterpris':92C,128C,154C,182C,205C 'exploit':132C,214C 'fed':65B 'flaw':30B 'graalvm':18B,40B,87C,91C,120C,127C,149C,153C,177C,181C,200C,204C 'host':28B 'impact':282C 'insert':166C 'integr':281C 'internet':265C 'java':2A,19B,21B,37B,74B,84C,97C,108C,146C,174C,197C,238C,245C,251C,270C 'java-web-servic':20B 'jdk':24B,89C,122C,151C,179C,202C 'l/a':294C 'l/i':293C 'l/pr':289C 'let':41B 'load':254C 'modifi':48B 'multipl':141C 'n':295C 'n/ac':288C 'n/s':291C 'n/ui':290C 'network':4A,47B,138C 'note':58B,209C 'oracl':1A,36B,83C,86C,90C,96C,107C,119C,126C,145C,148C,152C,173C,176C,180C,196C,199C,203C 'perf':113C 'product':94C 'protocol':142C 'reach':62B 'read':7A,50B,190C 'reli':267C 'result':162C 'run':243C,256C 'runtim':25B 'sandbox':73B,244C,250C,271C 'score':277C 'se':3A,38B,85C,98C,109C,147C,175C,198C 'secur':33B,100C,273C 'self':27B 'self-host':26B 'servic':23B,69B,226C 'specifi':220C 'start':76B,247C 'subset':52B,194C 'success':156C 'suppli':228C 'support':101C 'typic':240C 'u/c':292C 'unauthent':43B,135C 'unauthor':164C,189C 'untrust':257C 'updat':165C 'use':216C 'vector':284C 'version':102C 'via':140C 'vulner':80C,133C,160C,211C,234C 'web':22B,68B,75B,225C,246C 'well':187C","nicknames":[],"mitigations":[],"who_affected":"Any system running an affected Oracle Java SE or GraalVM build that exposes Java code reachable from the network, such as web services that pass input to the vulnerable Security APIs. Client deployments running untrusted code in sandboxed Web Start or applets are also in scope. Systems on patched builds, or with no network-facing Java code, can deprioritise this.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-20T22:20:06+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N","cvss_by":"secalert_us@oracle.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-87294","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-87294","severity":null,"published_at":"2026-10-20T22:20:06+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"}