Vulnerability · Published Mar 26, 2026 · Assigned by Go
CVE-2026-32284Denial of service in github.com/shamaton/msgpack
High 7.5
In plain English
A high-severity security flaw in github.com/shamaton/msgpack from github.com/shamaton/msgpack. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 37% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.4%top 63.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
The msgpack decoder fails to properly validate the input buffer length when processing truncated fixext data (format codes 0xd4-0xd8). This can lead to an out-of-bounds read and a runtime panic, allowing a denial of service attack.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/shamaton/msgpack | no fix listed | GO-2026-4740 |
| Go | github.com/shamaton/msgpack | no fix listed | GO-2026-4513 |
| Go | github.com/shamaton/msgpack/v2 | no fix listed | GO-2026-4740 |
| Go | github.com/shamaton/msgpack/v2 | no fix listed | GHSA-h9q6-hc68-35rp |
| Go | github.com/shamaton/msgpack/v2 | 2.4.1 | GO-2026-4513 |
| Go | github.com/shamaton/msgpack/v3 | no fix listed | GO-2026-4740 |
| Go | github.com/shamaton/msgpack/v3 | no fix listed | GHSA-h9q6-hc68-35rp |
| Go | github.com/shamaton/msgpack/v3 | 3.1.1 | GO-2026-4513 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| github.com/shamaton/msgpack | github.com/shamaton/msgpack | see references |
| github.com/shamaton/msgpack/v2 | github.com/shamaton/msgpack/v2 | 0 – before 2.4.1 |
| github.com/shamaton/msgpack/v3 | github.com/shamaton/msgpack/v3 | 0 – before 3.1.1 |