CVE-2026-104016
HIGHDescription
ProtobufParser parses length-prefixed protobuf string and bytes fields by checking (_inputPtr + len) <= _inputEnd and then, on the fast path, calling _finishShortText(len). Both use 32-bit signed integer arithmetic. When an attacker supplies a varint decoding to a length near Integer.MAX_VALUE, _inputPtr + len overflows to a negative value, the bounds check passes, and _finishShortText(len) reaches TextBuffer.expandCurrentSegment(len), which performs Arrays.copyOf with no cap and throws OutOfMemoryError: Requested array size exceeds VM limit. The JVM refuses arrays larger than Integer.MAX_VALUE - 8 before consulting available heap, so -Xmx tuning does not mitigate the issue. StreamReadConstraints.maxStringLength and maxDocumentLength do not gate this path: a 33-byte payload is far below any document-length cap and the string-length check does not fire before the allocation. This was confirmed empirically against shipping artifacts with maxStringLength, maxDocumentLength and maxNestingDepth all configured. A February 2026 hardening commit added the equivalent overflow guard to the packed-array-length and message-length paths but left the string-length call sites unguarded. No privileges or user interaction beyond the ability to submit data for parsing are required.
Is your site exposed to CVE-2026-104016?
Run a free security scan — no signup, results in seconds.
CVSS v3.1 Score
Weakness Type (CWE)
References
Frequently Asked Questions
What is CVE-2026-104016? +
How severe is CVE-2026-104016? +
How do I check if I'm vulnerable to CVE-2026-104016? +
Related Vulnerabilities
diff3 tool from GNU diffutils is vulnerable to a heap‑based buffer overflow due to multiple signed integer overflows in line‑mapping …
Out-of-bounds array write in Xpdf 4.05 and earlier, due to incorrect integer overflow checking in the PostScript function interpreter code.
z2d is a pure Zig 2D graphics library. Versions of z2d after `0.5.1` and up to and including `0.6.0`, when …
If a SCSI READ(10) command is initiated via USB using the largest LBA (0xFFFFFFFF) with it's default block size of …
Integer Overflow or Wraparound vulnerability in dragonflydb dragonfly (src/redis/lua/struct modules). This vulnerability is associated with program files lua_struct.C. This issue …
An integer overflow exists in the FTS5 https://sqlite.org/fts5.html extension. It occurs when the size of an array of tombstone pointers …