How severe is CVE-2021-36153?

CVE-2021-36153 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-36153 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-36153?

CVE-2021-36153 primarily affects Linuxfoundation Grpc Swift. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-36153?

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-2021-36153 published?

CVE-2021-36153 was published on 2021-07-09 and last updated on 2026-06-17.

CVE-2021-36153

CVE-2021-36153 is a high-severity vulnerability in Linuxfoundation Grpc Swift with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Linuxfoundation Grpc Swift
Published: 2021-07-09
Last modified: 2026-06-17

Description

Mismanaged state in GRPCWebToHTTP2ServerCodec.swift in gRPC Swift 1.1.0 and 1.1.1 allows remote attackers to deny service by sending malformed requests.

Frequently asked questions

What is CVE-2021-36153?: Mismanaged state in GRPCWebToHTTP2ServerCodec.swift in gRPC Swift 1.1.0 and 1.1.1 allows remote attackers to deny service by sending malformed requests.
How severe is CVE-2021-36153?: CVE-2021-36153 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-36153 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36153?: CVE-2021-36153 primarily affects Linuxfoundation Grpc Swift. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-36153?: 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-2021-36153 published?: CVE-2021-36153 was published on 2021-07-09 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:linuxfoundation:grpc_swift:1.1.0:*:*:*:*:*:*:*
cpe:2.3:a:linuxfoundation:grpc_swift:1.1.1:*:*:*:*:*:*:*

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