CVE-2021-36154

HIGHNVD 7.57.5—

7.5

HTTP2ToRawGRPCServerCodec in gRPC Swift 1.1.1 and earlier allows remote attackers to deny service via the delivery of many small messages within a single HTTP/2 frame, leading to Uncontrolled Recursion and stack consumption.

CVSS v3: 7.5
EG Score: 7.5(medium)
EPSS: 75.1%
KEV: Not listed

Published

July 9, 2021

Last Modified

November 21, 2024

References (6)

cve@mitrehttps://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35274
cve@mitrehttps://github.com/grpc/grpc-swift/releases
cve@mitrehttps://github.com/grpc/grpc-swift/security/advisories/GHSA-4rhq-vq24-88gw
af854a3a-2127-422b-91ae-364da2661108https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=35274
af854a3a-2127-422b-91ae-364da2661108https://github.com/grpc/grpc-swift/releases
af854a3a-2127-422b-91ae-364da2661108https://github.com/grpc/grpc-swift/security/advisories/GHSA-4rhq-vq24-88gw

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-674Uncontrolled Recursion

Data Freshness Timeline

(refreshed 12× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

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Frequently asked(5)

What is CVE-2021-36154?

CVE-2021-36154 is a high vulnerability published on July 9, 2021. HTTP2ToRawGRPCServerCodec in gRPC Swift 1.1.1 and earlier allows remote attackers to deny service via the delivery of many small messages within a single HTTP/2 frame, leading to Uncontrolled Recursion and stack consumption.

When was CVE-2021-36154 disclosed?

CVE-2021-36154 was first published in the National Vulnerability Database on July 9, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2021-36154 actively exploited?

CVE-2021-36154 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 75.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2021-36154?

CVE-2021-36154 has a CVSS v3 base score of 7.5 (NVD).

How do I remediate CVE-2021-36154?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-36154, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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CVE-2021-36154

📅 Published

🔄 Last Modified

🔗 References (6)