Vulnerability · Published Apr 24, 2026 · Assigned by GitHub_M
CVE-2026-33524Zserio: Integer Overflow in BitStreamReader and Unbounded Memory Allocation in Deserialization
High 7.5
In plain English
A high-severity security flaw in zserio from ndsev. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.3%top 74.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Zserio is a framework for serializing structured data with a compact and efficient way with low overhead. Prior to 2.18.1, a crafted payload as small as 4-5 bytes can force memory allocations of up to 16 GB, crashing any process with an OOM error (Denial of Service). This vulnerability is fixed in 2.18.1.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | io.github.ndsev:zserio-runtime | 2.18.1 | GHSA-cwq5-8pvq-j65j |
Affected products (as reported)
Weakness: CWE-789 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/ndsev/zserio/security/advisories/GHSA-cwq5-8pvq-j65j x_refsource_CONFIRM