Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Wire's wire-runtime package (Maven com.squareup.wire:wire-runtime) versions below 6.4.5 and from 7.0.0-alpha01 up to but not including 7.0.0-alpha04 are affected. An attacker who can supply protobuf bytes to an application decoding them with the Kotlin ProtoAdapter.decode(ByteArray) or decode(ByteString) fast path can send a short malformed payload with an oversized length, causing decoding to throw unchecked runtime exceptions instead of normal decode errors, which can crash request handling or the process. Upgrade to 6.4.5 or 7.0.0-alpha04.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 7.5 | High | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0082, the 57th percentile, on 6 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:16 UTC First seen by agentprime
- 31 Oct 2026, 14:16 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-9rm7-3qhh-h2mc
- OSV: GHSA-9rm7-3qhh-h2mc
- github.com/square/wire/security/advisories/GHSA-9rm7-3qhh-h2mc
- nvd.nist.gov/vuln/detail/CVE-2026-63126
- github.com/square/wire/pull/3635
- github.com/square/wire/commit/082d5d83cec57ef68f1dd7d3e3d1d641c1fb670f
- github.com/square/wire/commit/25ebcabb9ab7f12d1d77af75ecbc51726fddc015
- github.com/square/wire
- github.com/square/wire/releases/tag/6.4.5
- github.com/square/wire/releases/tag/7.0.0-alpha04