High severity · published Jul 17, 2026
CVE-2026-45799
Wire: skipGroup() missing negative-length check allows 10-byte payload to crash any Wire-decoding service
7.5
CVSS
0.7%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WI
wire · square
< 6.3.0; >= 7.0.0-alpha01, < 7.0.0-alpha03 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-45799
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-45799
Patch
https://github.com/square/wire/commit/47d5b0dba53935d5332cd41a80a353b3fc90e7b0
Patch
https://github.com/square/wire/commit/e4e56fab38a547d9625f05c97f1d8f0bcc3a5773
Issue Tracking
https://github.com/square/wire/pull/3595
Issue Tracking
https://github.com/square/wire/pull/3597
Release Notes
https://github.com/square/wire/releases/tag/6.3.0
Release Notes
https://github.com/square/wire/releases/tag/7.0.0-alpha03
More from wire
7.5
CVE-2026-61695
Wire Swift runtime: negative LENGTH_DELIMITED length in skipGroup() crashes any protobuf-decoding service
7.5
CVE-2026-63126
Wire: Unauthenticated decoder crash via 32-bit length integer overflow in ByteArrayProtoReader32 (incomplete fix of CVE-2026-45799)
5.8
CVE-2024-58103
Square Wire before 5.2.0 does not enforce a recursion limit on nested groups in ByteArrayProtoReader32.kt and ProtoReader.kt