CVE-2026-32776

Process crash via uninitialized literal scanner call

Published Mar 16, 2026 · Updated Mar 16, 2026

NULL pointer dereference in Expat Project libexpat before 2.7.5 allows local users to crash a calling process via crafted XML. For an empty external parameter entity, entityValueInitProcessor reaches XmlEntityValueTok before encoding detection initializes the selected literalScanners entry, causing a call through NULL. Applications are exposed only when they use both XML_ExternalEntityParserCreate and XML_SetParamEntityParsing; the bounded effect is a calling-process crash.

CVSS severity4.0
Medium
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in Expat Project libexpat before 2.7.5 allows local users to crash a calling process via crafted XML. For an empty external parameter entity, entityValueInitProcessor reaches XmlEntityValueTok before encoding detection initializes the selected literalScanners entry, causing a call through NULL. Applications are exposed only when they use both XML_ExternalEntityParserCreate and XML_SetParamEntityParsing; the bounded effect is a calling-process crash.

The record

CVE
CVE-2026-32776
Published
Mar 16, 2026
Updated
Mar 16, 2026
Vendor
Expat Project
Product
libexpat
Classifications
CWE-476, T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 16, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 16, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <2.7.5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Expat Project · libexpatversion=0 <2.7.5

Published CVSS scores

4.0MITRECVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation

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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