CVE-2019-18836 — Envoy 1

Envoy 1.12.0 allows a remote denial of service because of resource loops, as demonstrated by a single idle TCP connection being able to keep a worker thread in an infinite busy loop when continue_on_listener_filters_timeout is used."

01What is this vulnerability?

Envoy 1.12.0 allows a remote denial of service because of resource loops, as demonstrated by a single idle TCP connection being able to keep a worker thread in an infinite busy loop when continue_on_listener_filters_timeout is used."

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2019-11-11T00:17:35.000Z
• Last modified: 2024-08-05T02:02:39.447Z

09References

• groups.google.com — https://groups.google.com/forum/#%21forum/envoy-users
• blog.envoyproxy.io — https://blog.envoyproxy.io
• github.com — https://github.com/envoyproxy/envoy/security/advisories/GHSA-3xvf-4396-cj46
• github.com — https://github.com/istio/istio/issues/18229