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Response snapshot Oct 28, 2026, 02:46 UTC

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VulnerabilityCVE-2026-110747

ProtobufParser._readStringKey() reads the length prefix of a protobuf map entry's string key into an attacker-controlled int and then checks (_inputPtr + len) <= _inputEnd using...

ProtobufParser._readStringKey() reads the length prefix of a protobuf map entry's string key into an attacker-controlled int and then checks (_inputPtr + len) <= _inputEnd using signed arithmetic. For values near Integer.

At a glance

Exploited
Not known
Severity
7.5 High (CVSS 3.1)
Chance of exploitation
Not estimated
Sources
1 source

What to do

Check the vendor advisory for affected versions and fixes.

Read NVD CVE-2026-110747 (opens a new tab)

What happened

ProtobufParser._readStringKey() reads the length prefix of a protobuf map entry's string key into an attacker-controlled int and then checks (_inputPtr + len) <= _inputEnd using signed arithmetic. For values near Integer.MAX_VALUE the addition overflows to a negative value and the check passes even when the input contains no key data.

The parser then calls _finishShortText(len), which expands the text buffer to the declared length via TextBuffer.expandCurrentSegment and Arrays.copyOf, throwing OutOfMemoryError: Requested array size exceeds VM limit.

An 8-byte malformed message containing a map entry with a declared key length of 0x7FFFFFFF is sufficient. Configured StreamReadConstraints, including maxStringLength, maxNameLength, maxDocumentLength and maxNestingDepth, do not prevent the failure. Applications running with -XX:+ExitOnOutOfMemoryError terminate the JVM.

This is the same integer-overflow pattern addressed for other call sites in the remediation associated with CVE-2026-104016 and CVE-2026-104017; the map-key call site was corrected on the 3.x branches only, leaving the corresponding 2.x branches unguarded. Release lines 2.18, 2.19 and 2.20 do not contain _readStringKey() and are not affected by this vector.

Continue reading

No privileges or user interaction beyond the ability to submit data for parsing are required. The 3.0 release line and 3.1.0-3.1.5 / 3.2.0-3.2.1 do not contain _readStringKey() and are therefore not affected; the method first appears in 3.1.6 and 3.2.2, mirroring its introduction at 2.21.6 on the 2.x side.

Scores and how they were measured

CVSS base severity

7.5

Version 3.1As of

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Measurement source (opens a new tab)

How bad it is if exploited. Not a prediction of exploitation or proof you are exposed.

EPSS probability

Not available

A model's estimate of exploitation in the next 30 days, not certainty or your own risk.

Sources

  1. Primary source

    NVD CVE-2026-110747 (opens a new tab)

    NVD record: description, CVSS (the CNA score is preferred), affected products, and publication date. Not evidence of exploitation.

    Published Checked

  2. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  3. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

  4. Primary source

    NVD CVE API 2.0 (opens a new tab)

    The NVD API page that supplied this CVE record.

    Published Date not suppliedChecked

Cite this record

For factual claims, cite the primary sources above; cite KEVWire for its compilation, dates, and classifications.

APA

KEVWire. (2026, October 28). ProtobufParser._readStringKey() reads the length prefix of a protobuf map entry's string key into an attacker-controlled int and then checks (_inputPtr + len) <= _inputEnd using... (CVE-2026-110747). https://kevwire.com/record/CVE-2026-110747

MLA

"ProtobufParser._readStringKey() reads the length prefix of a protobuf map entry's string key into an attacker-controlled int and then checks (_inputPtr + len) <= _inputEnd using... (CVE-2026-110747)." KEVWire, 28 Oct. 2026, kevwire.com/record/CVE-2026-110747.

Chicago

KEVWire. "ProtobufParser._readStringKey() reads the length prefix of a protobuf map entry's string key into an attacker-controlled int and then checks (_inputPtr + len) <= _inputEnd using... (CVE-2026-110747)." Last modified October 28, 2026. https://kevwire.com/record/CVE-2026-110747.

Evidence summary (plain text)

ProtobufParser._readStringKey() reads the length prefix of a protobuf map entry's string key into an attacker-controlled int and then checks (_inputPtr + len) <= _inputEnd using... (Oct 28, 2026).
ProtobufParser._readStringKey() reads the length prefix of a protobuf map entry's string key into an attacker-controlled int and then checks (_inputPtr + len) <= _inputEnd using signed arithmetic. For values near Integer.MAX_VALUE the addition overflows to a negative value and the check passes even when the input contains no key data. The parser then calls _finishShortText(len), which expands the text buffer to the declared length via TextBuffer.expandCurrentSegment and Arrays.copyOf, throwing OutOfMemoryError: Requested array size exceeds VM limit.
CVSS 7.5 (version 3.1; evidence as of Oct 28, 2026; https://nvd.nist.gov/vuln/detail/CVE-2026-110747).
Sources:
NVD CVE-2026-110747: https://nvd.nist.gov/vuln/detail/CVE-2026-110747
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-28T01:10:57.689Z&lastModEndDate=2026-10-28T02:40:57.490Z&resultsPerPage=500&startIndex=0
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-28T00:35:57.457Z&lastModEndDate=2026-10-28T02:10:57.168Z&resultsPerPage=500&startIndex=0
NVD CVE API 2.0: https://services.nvd.nist.gov/rest/json/cves/2.0?lastModStartDate=2026-10-28T00:06:00.935Z&lastModEndDate=2026-10-28T01:35:55.761Z&resultsPerPage=500&startIndex=0
Record ID: CVE-2026-110747.
Record origin: Ingested record.
AI evidence: Not assessed.
Known exploitation: Not assessed.
Zero-day status: Not assessed. KEV membership alone does not establish zero-day status.
About this data

This record was ingested from a data source. Retrieved: Oct 28, 2026, 02:40 UTC. Ingestion is not an independent editorial investigation.

NVD status: Received. Publication in the NVD is not evidence of exploitation.

A CISA KEV listing documents known exploitation, not necessarily a zero-day; absence from the catalog does not prove a vulnerability has never been exploited.

Technology tags indicate possible relevance, not verified exposure. Confirm the affected product, version, and configuration against your own inventory; KEVWire does not scan your systems.

A personal reading checklist on this device, not verified remediation.

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Record details

Record detail