CVE-2026-88389

Application termination via raw-string iterator corruption

Published Sep 25, 2026 · Updated Sep 25, 2026

NULL pointer dereference in Espruino 2v29 allows attackers to terminate the application with crafted raw or binary string input. In jslGetRawString(), the lexer passes a NULL iterator target to jsvLockAgain(), which writes through that pointer when assertions are absent. Exploitation requires a RELEASE or NO_ASSERT build and causes memory corruption followed by application termination, with no published evidence of code execution.

CVSS severityUnavailable
Unscored
EPSS probability0.11%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in Espruino 2v29 allows attackers to terminate the application with crafted raw or binary string input. In jslGetRawString(), the lexer passes a NULL iterator target to jsvLockAgain(), which writes through that pointer when assertions are absent. Exploitation requires a RELEASE or NO_ASSERT build and causes memory corruption followed by application termination, with no published evidence of code execution.

The record

CVE
CVE-2026-88389
Published
Sep 25, 2026
Updated
Sep 25, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1499
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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