Envoy Gateway Log Injection Vulnerability

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Envoy Gateway is an open source project for managing Envoy Proxy as a standalone or Kubernetes-based application gateway. In all Envoy Gateway versions prior to 1.2.7 and 1.3.1 a default Envoy Proxy access log configuration is used. This format is vulnerable to log injection attacks. If the attacker uses a specially crafted user-agent which performs json injection, then he could add and overwrite fields to the access log. This vulnerability is fixed in 1.3.1 and 1.2.7. One can overwrite the old text based default format with JSON formatter by modifying the "EnvoyProxy.spec.telemetry.accessLog" setting.

Source published

6 Mar 2025 18:46:23 UTC

Source modified

6 Mar 2025 20:34:27 UTC

Saved here

23 Oct 2026 15:48:27 UTC

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CVE Program Terms of Use

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Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 3.1 · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Envoy Gateway is an open source project for managing Envoy Proxy as a standalone or Kubernetes-based application gateway. In all Envoy Gateway versions prior to 1.2.7 and 1.3.1 a default Envoy Proxy access log configuration is used. This format is vulnerable to log injection attacks. If the attacker uses a specially crafted user-agent which performs json injection, then he could add and overwrite fields to the access log. This vulnerability is fixed in 1.3.1 and 1.2.7. One can overwrite the old text based default format with JSON formatter by modifying the "EnvoyProxy.spec.telemetry.accessLog" setting.

Source published

Mar 6, 2025, 6:46:23 PM (timezone not stated)

Source modified

Mar 6, 2025, 8:34:27 PM (timezone not stated)

Saved here

15 Nov 2026 05:34:57 UTC

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ENISA EUVD · source terms and attribution apply

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Source: euvd · ENISA EUVD · source terms and attribution apply. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

EUVD CVSS 3.1 · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Envoy Gateway is an open source project for managing Envoy Proxy as a standalone or Kubernetes-based application gateway. In all Envoy Gateway versions prior to 1.2.7 and 1.3.1 a default Envoy Proxy access log configuration is used. This format is vulnerable to log injection attacks. If the attacker uses a specially crafted user-agent which performs json injection, then he could add and overwrite fields to the access log. This vulnerability is fixed in 1.3.1 and 1.2.7. One can overwrite the old text based default format with JSON formatter by modifying the "EnvoyProxy.spec.telemetry.accessLog" setting.

Source published

6 Mar 2025 19:15:27 UTC

Source modified

17 Jun 2026 09:00:38 UTC

Saved here

25 Oct 2026 01:17:35 UTC

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NIST NVD usage terms; underlying source attribution retained

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Source: nvd · NIST NVD usage terms; underlying source attribution retained. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 3.1 · [email protected] · Secondary · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

### Impact In all Envoy Gateway versions prior to 1.2.7 and 1.3.1 a default Envoy Proxy access log configuration is used. This format is vulnerable to log injection attacks. If the attacker uses a specially crafted user-agent which performs json injection, then he could add and overwrite fields to the access log. Examples of attacks include: - Using following string as user agent : `HELLO-WORLD", "evil-ip": "1.1.1.1", "x-forwarded-for": "1.1.1.1` would lead to setting of new access log properties and overwrite of existing properties. Existing properties such as the value of the X-Forwarded-For header may have importance for security analysis of access logs, and their overwrite can be used to hide malicious activity. - Using the following string as user-agent : `"` which renders an invalid json document. The invalid document may fail to be processed by observability solutions, which would allow attacker to hide malicious activity. ### Patches 1.3.1, 1.2.7 ### Fix Using JSON format as the default format for access logs. The logged document will contain the same key and values as before. Only the order of properties is different inside the logged document. ### Workaround One can overwrite the old text based default format with JSON formatter by setting the following property: "EnvoyProxy.spec.telemetry.[accessLog](https://gateway.envoyproxy.io/v1.3/api/extension_types/#proxyaccesslog)" to ``` settings: - format: type: JSON json: start_time: '%START_TIME%' method: '%REQ(:METHOD)%' x-envoy-origin-path: '%REQ(X-ENVOY-ORIGINAL-PATH?:PATH)%' protocol: '%PROTOCOL%' response_code: '%RESPONSE_CODE%' response_flags: '%RESPONSE_FLAGS%' response_code_details: '%RESPONSE_CODE_DETAILS%' connection_termination_details: '%CONNECTION_TERMINATION_DETAILS%' upstream_transport_failure_reason: '%UPSTREAM_TRANSPORT_FAILURE_REASON%' bytes_received: '%BYTES_RECEIVED%' bytes_sent: '%BYTES_SENT%' duration: '%DURATION%' x-envoy-upstream-service-time: '%RESP(X-ENVOY-UPSTREAM-SERVICE-TIME)%' x-forwarded-for: '%REQ(X-FORWARDED-FOR)%' user-agent: '%REQ(USER-AGENT)%' x-request-id: '%REQ(X-REQUEST-ID)%' :authority: '%REQ(:AUTHORITY)%' upstream_host: '%UPSTREAM_HOST%' upstream_cluster: '%UPSTREAM_CLUSTER%' upstream_local_address: '%UPSTREAM_LOCAL_ADDRESS%' downstream_local_address: '%DOWNSTREAM_LOCAL_ADDRESS%' downstream_remote_address: '%DOWNSTREAM_REMOTE_ADDRESS%' requested_server_name: '%REQUESTED_SERVER_NAME%' route_name: '%ROUTE_NAME%' ``` see API definition [here](https://gateway.envoyproxy.io/v1.3/api/extension_types/#proxyaccesslogformat) ### References _Are there any links users can visit to find out more?_

Source published

6 Mar 2025 19:11:39 UTC

Source modified

10 Sep 2026 03:50:56 UTC

Saved here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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Source: osv · GitHub Advisory Database · CC-BY-4.0. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Publisher rating · MODERATE

Envoy Gateway Log Injection Vulnerability in github.com/envoyproxy/gateway

Source published

10 Mar 2025 19:01:10 UTC

Source modified

4 Feb 2026 04:32:08 UTC

Saved here

24 Oct 2026 13:19:41 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

Source: osv · OSV · upstream source license applies. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.