Quick answers
- Is CVE-2026-102477 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-102477 being exploited in the wild.
- How severe is CVE-2026-102477?
- Medium severity, with a CVSS score of 5.9, published 15 October 2026.
- Which products and versions are affected?
- Eclipse Vert.X 4.0.0 to 4.5.34, 5.0.0 to 5.1.8, 5.2.0.
- Is there a fix for CVE-2026-102477?
- Yes: fixed in 4.5.35, 5.1.10, 5.2.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-102477 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-102477?
- Check whether you run Eclipse Vert.X at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: 4.5.35, 5.1.10, 5.2.1
Technical details
The gRPC server applies its per-message size limit to the compressed bytes received on the wire rather than to the decompressed content. An attacker can send a highly compressed message that passes the size check but expands to an arbitrarily large payload during decompression, bypassing the intended DoS protection. This is a classic compression bomb vulnerability affecting network services with no authentication or user interaction required.
Affected products
- Eclipse Vert.x 4.0.0 to 4.5.34, 5.0.0 to 5.1.8, 5.2.0
Timeline
- 2026-10-07: disclosed
- 2026-10-15: advisory