Zebra: addr/addrv2 Deserialization Resource Exhaustion_CVE-2026-40881

6.3 / 10

MEDIUM

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L

Description

ZEBRA is a Zcash node written entirely in Rust. Prior to zebrad version 4.3.0 and zebra-network version 5.0.1, when deserializing addr or addrv2 messages, which contain vectors of addresses, Zebra would fully deserialize them up to a maximum length (over 233,000) that was derived from the 2 MiB message size limit. This is much larger than the actual limit of 1,000 messages from the specification. Zebra would eventually check that limit but, at that point, the memory for the larger vector was already allocated. An attacker could cause out-of-memory aborts in Zebra by sending multiple such messages over different connections. This vulnerability is fixed in zebrad version 4.3.0 and zebra-network version 5.0.1.

Basic Information

ID CVE-2026-40881

Source GitHub_M

Published Apr 21, 2026 at 19:20

Modified Apr 21, 2026 at 20:36

Affected Product

Vendor ZcashFoundation

Product zebrad

Version < 4.3.1

Affected Versions ZcashFoundation zebrad < 4.3.1
ZcashFoundation zebra-network < 5.0.1

CWE Classification

CWE-770

References

github.com /ZcashFoundation/zebra/security/advisories/GHSA-xr93-pcq3-pxf8

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    "published": "2026-04-21T19:20:53.416Z",
    "modified": "2026-04-21T20:36:18.824Z",
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