CVE-2023-27487
CVE-2023-27487 is a high-severity vulnerability in Envoyproxy Envoy with a CVSS 3.x base score of 8.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.
Key facts
- Severity: High (CVSS 3.x base score 8.2)
- EPSS exploit prediction: 1% (46th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Envoyproxy Envoy
- Published:
- Last modified:
Description
Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, the client may bypass JSON Web Token (JWT) checks and forge fake original paths. The header `x-envoy-original-path` should be an internal header, but Envoy does not remove this header from the request at the beginning of request processing when it is sent from an untrusted client. The faked header would then be used for trace logs and grpc logs, as well as used in the URL used for `jwt_authn` checks if the `jwt_authn` filter is used, and any other upstream use of the x-envoy-original-path header. Attackers may forge a trusted `x-envoy-original-path` header. Versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9 have patches for this issue.
Frequently asked questions
- What is CVE-2023-27487?
- Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, the client may bypass JSON Web Token (JWT) checks and forge fake original paths. The header `x-envoy-original-path` should be an internal header, but Envoy does not remove this header from the request at the beginning of request processing when it is sent from an untrusted client. The faked header would then be used for trace logs and grpc logs, as well as used in the URL used for `jwt_authn` checks if the `jwt_authn` filter is used, and any other upstream use of the x-envoy-original-path header. Attackers may forge a trusted `x-envoy-original-path` header. Versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9 have patches for this issue.
- How severe is CVE-2023-27487?
- CVE-2023-27487 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
- Is CVE-2023-27487 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-27487?
- CVE-2023-27487 affects Envoyproxy Envoy. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2023-27487?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2023-27487 published?
- CVE-2023-27487 was published on 2023-04-04 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
More vulnerabilities in Envoyproxy Envoy
- CVE-2022-29226 — Critical (CVSS 10.0): Envoy is a cloud-native high-performance proxy. In versions prior to 1.22.1 the OAuth filter implementation does not…
- CVE-2019-18802 — Critical (CVSS 9.8): An issue was discovered in Envoy 1.12.0. An untrusted remote client may send an HTTP header (such as Host) with…
- CVE-2019-18801 — Critical (CVSS 9.8): An issue was discovered in Envoy 1.12.0. An untrusted remote client may send HTTP/2 requests that write to the heap…
- CVE-2020-35470 — High (CVSS 8.8): Envoy before 1.16.1 logs an incorrect downstream address because it considers only the directly connected peer, not the…
- CVE-2024-23324 — High (CVSS 8.6): Envoy is a high-performance edge/middle/service proxy. External authentication can be bypassed by downstream…
- CVE-2023-35941 — High (CVSS 8.6): Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to versions 1.27.0,…
All CVEs affecting Envoyproxy Envoy →
Other CWE-20 (Improper Input Validation) vulnerabilities
- CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
- CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
- CVE-2026-48277 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
- CVE-2026-48055 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download any video media. In versions 2.4.0 and…
- CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
- CVE-2026-33587 — Critical (CVSS 10.0): Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and…
Browse all CWE-20 (Improper Input Validation) vulnerabilities →