Vulnerability in Square Wire
CVE-2026-45799
Wire provides gRPC and protocol buffers for Android, Kotlin, Swift, and Java. Prior to 6.3.0 and 7.0.0-alpha03, ByteArrayProtoReader32.skipGroup() and ProtoReader.skipGroup() in wire-runtime do not validate that a LENGTH_DELIMITED field length is non-negative before skip(), allowing a crafted protobuf varint encoding -128 as a signed Int to make skip(-128) move the internal position negative and make the next readByte() throw ArrayIndexOutOfBoundsException instead of the documented IOException or ProtocolException, which can crash services using ProtoAdapter.decode(byte[]) on untrusted payloads. This issue is fixed in versions 6.3.0 and 7.0.0-alpha03.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.007 (53.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 53.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.007 · change: +0.002
Affected products
- Square Wire — versions < 6.3.0, >= 7.0.0-alpha01, < 7.0.0-alpha03
- Squareup Wire — versions 7.0.0
Weakness classification (CWE)
References
- github.com/square/wire/commit/47d5b0dba53935d5332cd41a80a353b3fc90e7b0 (Patch)
- github.com/square/wire/commit/e4e56fab38a547d9625f05c97f1d8f0bcc3a5773 (Patch)
- github.com/square/wire/pull/3595 (Issue Tracking)
- github.com/square/wire/pull/3597 (Issue Tracking)
- github.com/square/wire/releases/tag/6.3.0 (Release Notes)
- github.com/square/wire/releases/tag/7.0.0-alpha03 (Release Notes)
- github.com/square/wire/security/advisories/GHSA-7xpr-hc2w-34m9 (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-45799?
- CVE-2026-45799 is a high-severity vulnerability in Square Wire, classified under Improper Validation of Array Index. CVSS score: 7.5/10. Published 2026-07-17.
- How severe is CVE-2026-45799?
- High severity. CVSS v3 base score is 7.5 out of 10.