{"id":"CVE-2021-39156","aliases":["EUVD-2021-1754","GHSA-hqxw-mm44-gc4r","RHSA-2021:3272","RHSA-2021:3273"],"status":"published","title":"Fragments in Path May Lead to Authorization Policy Bypass","description":"Istio is an open source platform for providing a uniform way to integrate microservices, manage traffic flow across microservices, enforce policies and aggregate telemetry data. Istio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio’s URI path based authorization policies. Patches are available in Istio 1.11.1, Istio 1.10.4 and Istio 1.9.8. As a work around a Lua filter may be written to normalize the path.","severity":{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.01177,"percentile":0.67995,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":true},"cwes":["CWE-706","CWE-863"],"published":"2021-08-24T22:30:12Z","modified":"2026-10-20T10:54:53Z","exploits":[{"source":"pocgithub","id":"mostafaanouarghorab/MicroserviceCVE-2021-39156","title":"mostafaanouarghorab/MicroserviceCVE-2021-39156","date":"2026-03-26","url":"https://github.com/mostafaanouarghorab/MicroserviceCVE-2021-39156"}],"fixes":[{"ecosystem":"Go","package":"istio.io/istio","fixed_in":["1.9.8","1.10.4","1.11.1"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"Go","package":"istio.io/istio","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.9.8"}]}]},{"source":"ghsa","ecosystem":"Go","package":"istio.io/istio","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.10.0"},{"fixed":"1.10.4"}]}]},{"source":"ghsa","ecosystem":"Go","package":"istio.io/istio","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.11.0"},{"last_affected":"1.11.0"},{"fixed":"1.11.1"}]}],"versions":["1.11.0"]},{"source":"osv","ecosystem":"Go","package":"istio.io/istio","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.9.8"}]}]},{"source":"osv","ecosystem":"Go","package":"istio.io/istio","ranges":[{"type":"SEMVER","events":[{"introduced":"1.10.0"},{"fixed":"1.10.4"}]}]},{"source":"osv","ecosystem":"Go","package":"istio.io/istio","ranges":[{"type":"SEMVER","events":[{"introduced":"1.11.0"},{"fixed":"1.11.1"}]}],"versions":["1.11.0"]},{"source":"osv","ecosystem":"Red Hat:service_mesh:2.0::el8","package":"servicemesh-proxy","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:2.0.7-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:2.0::el8","package":"servicemesh","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:2.0.7-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:2.0::el8","package":"servicemesh-istioctl","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:2.0.7-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:2.0::el8","package":"servicemesh-mixc","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:2.0.7-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:2.0::el8","package":"servicemesh-mixs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:2.0.7-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:2.0::el8","package":"servicemesh-pilot-agent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:2.0.7-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:2.0::el8","package":"servicemesh-pilot-discovery","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:2.0.7-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh-proxy","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-2.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh-citadel","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh-galley","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh-istioctl","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh-mixc","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh-mixs","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh-pilot-agent","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh-pilot-discovery","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-3.el8"}]}],"bundled":5},{"source":"osv","ecosystem":"Red Hat:service_mesh:1.1::el8","package":"servicemesh-sidecar-injector","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0:1.1.17-3.el8"}]}],"bundled":5}],"products":[{"vendor":"istio","product":"istio"}],"references":[{"url":"https://github.com/istio/istio/security/advisories/GHSA-hqxw-mm44-gc4r","tags":["x_refsource_CONFIRM","x_transferred","Third Party Advisory","advisory","web"]},{"url":"https://istio.io/latest/news/security/istio-security-2021-008","tags":["x_refsource_MISC","x_transferred","Vendor Advisory","advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-39156","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-hqxw-mm44-gc4r"},{"url":"https://github.com/istio/istio","tags":["package"]},{"url":"https://access.redhat.com/errata/RHSA-2021:3272","tags":["advisory"]},{"url":"https://access.redhat.com/security/updates/classification/#important","tags":["article"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1996915","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1996929","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1996933","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1996934","tags":["report"]},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=1996935","tags":["report"]},{"url":"https://security.access.redhat.com/data/csaf/v2/advisories/2021/rhsa-2021_3272.json","tags":["advisory"]},{"url":"https://access.redhat.com/security/cve/CVE-2021-32777","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-32777","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-32777","tags":["advisory"]},{"url":"https://istio.io/latest/news/security/istio-security-2021-008/","tags":["article"]},{"url":"https://access.redhat.com/security/cve/CVE-2021-32779","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-32779","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-32779","tags":["advisory"]},{"url":"https://access.redhat.com/security/cve/CVE-2021-32781","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-32781","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-32781","tags":["advisory"]},{"url":"https://access.redhat.com/security/cve/CVE-2021-39155","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-39155","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-39155","tags":["advisory"]},{"url":"https://access.redhat.com/security/cve/CVE-2021-39156","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-39156","tags":["advisory"]},{"url":"https://access.redhat.com/errata/RHSA-2021:3273","tags":["advisory"]},{"url":"https://security.access.redhat.com/data/csaf/v2/advisories/2021/rhsa-2021_3273.json","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2021-39156","title":"Fragments in Path May Lead to Authorization Policy Bypass","description":"Istio is an open source platform for providing a uniform way to integrate microservices, manage traffic flow across microservices, enforce policies and aggregate telemetry data. Istio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio’s URI path based authorization policies. Patches are available in Istio 1.11.1, Istio 1.10.4 and Istio 1.9.8. As a work around a Lua filter may be written to normalize the path.","status":"published","published":"2021-08-24T22:30:12Z","modified":"2024-08-04T01:58:18.136Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","level":"high","assessor":"cna"}],"cwes":["CWE-863"],"updated_at":"2026-11-02T14:33:09.540052Z"}],"euvd":[{"id":"EUVD-2021-1754","description":"Istio is an open source platform for providing a uniform way to integrate microservices, manage traffic flow across microservices, enforce policies and aggregate telemetry data. Istio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio’s URI path based authorization policies. Patches are available in Istio 1.11.1, Istio 1.10.4 and Istio 1.9.8. As a work around a Lua filter may be written to normalize the path.","status":"published","published":"2021-08-24T22:30:12Z","modified":"2024-08-04T01:58:18Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","level":"high"}],"updated_at":"2026-11-03T03:24:24.305495Z"}],"ghsa":[{"id":"GHSA-hqxw-mm44-gc4r","title":"Istio Fragments in Path May Lead to Authorization Policy Bypass","description":"### Impact\nIstio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio’s URI path based authorization policies. \n\n### Patches\n* Istio 1.11.1 and above\n* Istio 1.10.4 and above\n* Istio 1.9.8 and above\n\n### Workarounds\nA Lua filter may be written to normalize the path.  This is similar to the Path normalization presented in the [Security Best Practices](https://istio.io/latest/docs/ops/best-practices/security/#case-normalization) guide.\n\n### References\nMore details can be found in the [Istio Security Bulletin](https://istio.io/latest/news/security/istio-security-2021-008)\n\n### For more information\nIf you have any questions or comments about this advisory, please email us at istio-security-vulnerability-reports@googlegroups.com\n","status":"published","published":"2021-08-30T16:16:14Z","modified":"2023-01-27T05:00:52Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-706","CWE-863"],"updated_at":"2026-11-02T14:36:15.574072Z"}],"nvd":[{"id":"CVE-2021-39156","description":"Istio is an open source platform for providing a uniform way to integrate microservices, manage traffic flow across microservices, enforce policies and aggregate telemetry data. Istio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio’s URI path based authorization policies. Patches are available in Istio 1.11.1, Istio 1.10.4 and Istio 1.9.8. As a work around a Lua filter may be written to normalize the path.","status":"published","published":"2021-08-24T23:15:10.413Z","modified":"2026-06-17T04:03:12.743Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","level":"high","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:P/I:N/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-863","CWE-706"],"updated_at":"2026-11-02T14:06:57.67549Z"}],"osv":[{"id":"CVE-2021-39156","description":"Istio is an open source platform for providing a uniform way to integrate microservices, manage traffic flow across microservices, enforce policies and aggregate telemetry data. Istio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio’s URI path based authorization policies. Patches are available in Istio 1.11.1, Istio 1.10.4 and Istio 1.9.8. As a work around a Lua filter may be written to normalize the path.","status":"published","published":"2021-08-24T23:15:10.413Z","modified":"2026-10-20T10:54:53.413989729Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"high"}],"updated_at":"2026-11-02T15:44:20.843843Z"},{"id":"GHSA-hqxw-mm44-gc4r","title":"Istio Fragments in Path May Lead to Authorization Policy Bypass","description":"### Impact\nIstio 1.11.0, 1.10.3 and below, and 1.9.7 and below contain a remotely exploitable vulnerability where an HTTP request with `#fragment` in the path may bypass Istio’s URI path based authorization policies. \n\n### Patches\n* Istio 1.11.1 and above\n* Istio 1.10.4 and above\n* Istio 1.9.8 and above\n\n### Workarounds\nA Lua filter may be written to normalize the path.  This is similar to the Path normalization presented in the [Security Best Practices](https://istio.io/latest/docs/ops/best-practices/security/#case-normalization) guide.\n\n### References\nMore details can be found in the [Istio Security Bulletin](https://istio.io/latest/news/security/istio-security-2021-008)\n\n### For more information\nIf you have any questions or comments about this advisory, please email us at istio-security-vulnerability-reports@googlegroups.com\n","status":"published","published":"2021-08-30T16:16:14Z","modified":"2026-09-10T03:49:27.092104775Z","cvss":[{"version":"3.1","score":8.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N","level":"high"}],"cwes":["CWE-706","CWE-863"],"updated_at":"2026-11-02T15:46:49.621585Z"},{"id":"RHSA-2021:3272","title":"Red Hat Security Advisory: Red Hat OpenShift Service Mesh 2.0.7.1 security update","status":"published","published":"2024-09-16T06:20:24Z","modified":"2026-03-18T11:31:14.624752Z","cvss":[{"version":"3.1","score":8.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L","level":"high"}],"updated_at":"2026-11-02T15:53:08.619234Z"},{"id":"RHSA-2021:3273","title":"Red Hat Security Advisory: Red Hat OpenShift Service Mesh 1.1.17.1 security update","status":"published","published":"2024-09-16T06:20:31Z","modified":"2026-03-18T11:31:15.902321Z","cvss":[{"version":"3.1","score":8.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L","level":"high"}],"updated_at":"2026-11-02T15:53:08.619234Z"}]}}