CVE-2024-27919
Envoyproxy Envoy 1.29.0 … 1.29.1
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSummary
CVE-2024-27919 is a high-severity Detection of Error Condition Without Action (CWE-390) vulnerability in Envoyproxy Envoy. Its CVSS base score is 7.5 (High).
Operationally, ranked in the top 0.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
Envoy, the open-source edge and service proxy, contains a denial-of-service vulnerability in its HTTP/2 protocol stack affecting versions 1.29.0 and 1.29.1. The codec fails to reset a request once configured header-map limits are exceeded, allowing an unbounded sequence of CONTINUATION frames that lack the END_HEADERS flag and therefore consume memory without bound. The issue is a regression introduced only in those two releases and is tracked as CWE-390.
An unauthenticated network attacker can open an HTTP/2 connection to an affected Envoy instance and transmit a flood of such frames, driving memory exhaustion on the proxy and resulting in denial of service. The CVSS 7.5 vector reflects network attack reach, low complexity, and no required credentials or user interaction, with the sole impact being high availability loss.
Official guidance directs users to upgrade immediately to Envoy 1.29.2. Where an upgrade is not feasible, the documented workarounds are to downgrade to 1.28.1 or earlier or to disable HTTP/2 on downstream listeners. The fix is recorded in the project’s security advisory GHSA-gghf-vfxp-799r and the associated commit.
The EPSS score has remained at 0.2388 with no material post-disclosure increase.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2024-25106
Vulnerability Data
Envoy is a cloud-native, open-source edge and service proxy. In versions 1.29.0 and 1.29.1, theEnvoy HTTP/2 protocol stack is vulnerable to the flood of CONTINUATION frames. Envoy's HTTP/2 codec does not reset a request when header map limits have been…
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exceeded. This allows an attacker to send an sequence of CONTINUATION frames without the END_HEADERS bit set causing unlimited memory consumption. This can lead to denial of service through memory exhaustion. Users should upgrade to versions 1.29.2 to mitigate the effects of the CONTINUATION flood. Note that this vulnerability is a regression in Envoy version 1.29.0 and 1.29.1 only. As a workaround, downgrade to version 1.28.1 or earlier or disable HTTP/2 protocol for downstream connections.
- CWE(s)
Related Threats
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Developer testing and evaluation will surface code paths that detect errors yet perform no subsequent action.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Declaring incidents when criteria are met forces action on detected errors; eliminating the weakness helps but does not define the criteria themselves.
Triaging and validating reports compels follow-up on detections; removing the weakness supports but does not replace triage processes.
Analysis of detected events directly counters ignoring them, but does not guarantee every error condition is covered.
Monitoring produces detections, yet supplies no requirement to act on them.
Generating logs enables later action but does not enforce handling of each error condition.
Root-cause analysis of incidents requires acting on detected anomalies, though it applies after an incident is already declared.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Security testing can uncover missing error handling, but does not ensure the weakness is eliminated in production code.
Logging captures error conditions but does not guarantee subsequent handling or remediation.
Monitoring activities can detect errors, yet without defined response procedures the weakness persists.
Secure development lifecycle practices encourage proper error handling, but do not mandate it for every detected condition.
Secure coding standards typically require explicit error handling, reducing the likelihood of silent failures.