CVE-2026-59803

rpcx through 1.9.3, fixed in commit 047aec1, contains a denial-of-service vulnerability in protocol.Message.Decode (protocol/message.go). When a message has the compression flag set, the payload is gzip-decompressed via util.Unzip with no limit on the decompressed output size. The only built-in size guard, protocol.MaxMessageLength, is checked against the compressed on-the-wire frame length, not the decompressed size, so it provides no protection. Because decoding (and decompression) occurs in readRequest before authentication, a single unauthenticated connection can send a small (under 2 MB) gzip-compressed message that expands to gigabytes of heap allocation, leading to out-of-memory conditions and service unavailability.

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://github.com/smallnest/rpcx/commit/047aec18efa7d037105e2b72c36dd2ae05e1acc6
https://github.com/smallnest/rpcx/issues/942
https://github.com/smallnest/rpcx/pull/943
https://www.vulncheck.com/advisories/rpcx-denial-of-service-via-gzip-decompression-bomb-in-wire-protocol

Configurations

No configuration.

History

08 Jul 2026, 20:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-08 20:16

Updated : 2026-07-10 18:46

NVD link : CVE-2026-59803

Mitre link : CVE-2026-59803

CVE.ORG link : CVE-2026-59803

JSON object : View

Products Affected

No product.

CWE

CWE-409

Improper Handling of Highly Compressed Data (Data Amplification)

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