Cross-client header disclosure via HPACK desynchronization
Published Jun 9, 2023 · Updated Sep 26, 2024
Header parsing confusion in gRPC 1.53.0 and 1.54.0 through 1.54.1 allows remote attackers to expose other clients' headers via oversized headers. After a header-size error, the C-core HTTP/2 HPACK parser stops parsing the frame and skips its remaining dynamic-table mutations. A proxy-to-backend deployment can then decode later requests against a different table state, mixing headers across clients and enabling data exfiltration or privilege escalation.
Summary
What happened
Header parsing confusion in gRPC 1.53.0 and 1.54.0 through 1.54.1 allows remote attackers to expose other clients' headers via oversized headers. After a header-size error, the C-core HTTP/2 HPACK parser stops parsing the frame and skips its remaining dynamic-table mutations. A proxy-to-backend deployment can then decode later requests against a different table state, mixing headers across clients and enabling data exfiltration or privilege escalation.
The record
- CVE
- CVE-2023-32731
- Published
- Jun 9, 2023
- Updated
- Sep 26, 2024
- Vendor
- gRPC
- Product
- gRPC
- Classifications
- CWE-440
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 9, 2023CVE publishedPublication date reported by the CVE source.
- Sep 26, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=1.53 <=1.54
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What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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