Is CVE-2026-33666 actively exploited?

No active exploitation of CVE-2026-33666 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-33666 be exploited remotely?

Yes. CVE-2026-33666 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-33666?

CVE-2026-33666 has a CVSS score of 7.5 (HIGH).

HOME VULNERABILITIESCVE-2026-33666

HIGH

CVE-2026-33666

CWE-190Published: April 24, 2026· Updated: Apr 28, 2026

7.5

CVSS v3.1

EPSS:0.04%probability of exploitation in 30 daysPercentile:12.0th

Official Description

Zserio is a framework for serializing structured data with a compact and efficient way with low overhead. Prior to 2.18.1, in BitStreamReader.h readBytes() / readString(), the setBitPosition() bounds check receives the overflowed value and is completely bypassed. The code then reads len bytes (512 MB) from a buffer that is only a few bytes long, causing a segmentation fault. This vulnerability is fixed in 2.18.1.

NVD Source

Technical Analysis

CVE-2026-33666 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in availability disruption (denial of service), with a CVSS base score of 7.5.