CVE-2026-97032

HTTP/2 servers could end up crashing due to inadvertently modifying its HPACK encoder concurrently. This happens because the server modifies the HPACK encoder from two goroutines without synchronization: one uses the encoder to encode a HEADERS frame as part of a response sent to a client and the other modifies the encoder's table size when handling a SETTINGS frame containing SETTINGS_HEADER_TABLE_SIZE that a client sends. A malicious client can repeatedly send a request while changing the header table size to crash the server.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://go.dev/cl/847188
https://go.dev/cl/847313
https://go.dev/issue/81867
https://groups.google.com/g/golang-announce/c/U2fTuyDJznI
https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs
https://pkg.go.dev/vuln/GO-2026-6617

Configurations

No configuration.

History

15 Oct 2026, 16:18

Type	Values Removed	Values Added
CWE		CWE-362
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5

08 Oct 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-08 23:17

Updated : 2026-10-15 16:18

NVD link : CVE-2026-97032

Mitre link : CVE-2026-97032

CVE.ORG link : CVE-2026-97032

JSON object : View

Products Affected

No product.

CWE

CWE-362

Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

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"https://groups.google.com/g/golang-announce/c/U2fTuyDJznI", "source": "security@golang.org"}, {"url": "https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs", "source": "security@golang.org"}, {"url": "https://pkg.go.dev/vuln/GO-2026-6617", "source": "security@golang.org"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "description": [{"lang": "en", "value": "CWE-362"}]}], "descriptions": [{"lang": "en", "value": "HTTP/2 servers could end up crashing due to inadvertently modifying its HPACK encoder concurrently. This happens because the server modifies the HPACK encoder from two goroutines without synchronization: one uses the encoder to encode a HEADERS frame as part of a response sent to a client and the other modifies the encoder's table size when handling a SETTINGS frame containing SETTINGS_HEADER_TABLE_SIZE that a client sends. A malicious client can repeatedly send a request while changing the header table size to crash the server."}], "lastModified": "2026-10-15T16:18:24.967", "sourceIdentifier": "security@golang.org"}