{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2021-31920 in the wild and no public exploit code.","fix":"Upgrade to a fixed version.","what":"CVE-2021-31920 is a medium-severity vulnerability in n/a, published on 27 May 2021. Any signed-in user can exploit it over the network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2021-31920 and fix it if it is affected.\n\nWhat it is: CVE-2021-31920 is a medium-severity vulnerability in n/a, published on 27 May 2021. Any signed-in user can exploit it over the network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2021-31920 in the wild and no public exploit code.\n\nAffected product: n/a. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2021-31920/ (Markdown: https://insights.sbomify.com/CVE-2021-31920/index.md)","id":"CVE-2021-31920","markdown":"https://insights.sbomify.com/CVE-2021-31920/index.md","name":"CVE-2021-31920","record":{"aliases":[],"analysis":{"component_type":"cloud_service","fix_type":"upgrade","impacts":["security_bypass"],"network_reachable":"yes","non_default_config":true,"product_category":"Istio service mesh","requires_auth":"low_privilege","summary":"Attackers can bypass path-based authorization policies in Istio by using multiple slashes or escaped characters in HTTP requests.","user_interaction":"not_required","vuln_class":"security_feature_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"mitre","cpe":[{"product":"istio","vendor":"istio"}],"cvss":{"score":6.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","version":"3.1"},"cwes":[{"id":"CWE-706","name":"Use of Incorrectly-Resolved Name or Reference"}],"description":"Istio before 1.8.6 and 1.9.x before 1.9.5 has a remotely exploitable vulnerability where an HTTP request path with multiple slashes or escaped slash characters (%2F or %5C) could potentially bypass an Istio authorization policy when path based authorization rules are used.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"Security feature bypass in n/a","id":"CVE-2021-31920","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"security_feature_bypass","year":"2021"},"n_packages":0,"n_references":1,"next":{"headline":"Missing authorization in n/a","id":"CVE-2021-31921"},"packages":[],"prev":{"headline":"Use of uninitialized buffer in rkyv","id":"CVE-2021-31919"},"products":["n/a"],"published":"2021-05-27","related":[{"cvss_score":9.8,"headline":"Missing authorization in n/a","id":"CVE-2021-31921","kev_date_added":null,"published":"2021-06-02"},{"cvss_score":8.8,"headline":"Information disclosure in n/a","id":"CVE-2021-34824","kev_date_added":null,"published":"2021-06-29"},{"cvss_score":8.7,"headline":"Istio JWKS resolver to prevent private key material from being exposed when JWKS fetch fails.","id":"CVE-2026-31837","kev_date_added":null,"published":"2026-03-10"},{"cvss_score":8.3,"headline":"Authorization Policy Bypass Due to Case Insensitive Host Comparison","id":"CVE-2021-39155","kev_date_added":null,"published":"2021-08-24"},{"cvss_score":8.1,"headline":"Fragments in Path May Lead to Authorization Policy Bypass","id":"CVE-2021-39156","kev_date_added":null,"published":"2021-08-24"},{"cvss_score":7.6,"headline":"Istio may allow identity impersonation if user has localhost access","id":"CVE-2022-39388","kev_date_added":null,"published":"2022-11-10"},{"cvss_score":7.5,"headline":"Istio vulnerable to denial of service attack due to Golang Regex Library","id":"CVE-2022-39278","kev_date_added":null,"published":"2022-10-13"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2024-08-03","vendors":["n/a"]},"summary":"Attackers can bypass path-based authorization policies in Istio by using multiple slashes or escaped characters in HTTP requests.","url":"https://insights.sbomify.com/CVE-2021-31920/"}