CVE-2022-23990Network attack vector

Service interruption via unchecked element-name length accumulation

Published Jan 26, 2022 · Updated May 5, 2025

Integer overflow in Expat before 2.4.4 allows remote attackers to interrupt an XML-processing service with crafted element declarations. In doProlog, nameLen counts each element name before contentStringLen adds the result without checking whether the unsigned sum wraps. The target must process attacker-controlled XML containing sufficiently large element-type content; no confidentiality or integrity impact is reported.

CVSS severity7.5
High
EPSS probability3.99%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Integer overflow in Expat before 2.4.4 allows remote attackers to interrupt an XML-processing service with crafted element declarations. In doProlog, nameLen counts each element name before contentStringLen adds the result without checking whether the unsigned sum wraps. The target must process attacker-controlled XML containing sufficiently large element-type content; no confidentiality or integrity impact is reported.

The record

CVE
CVE-2022-23990
Published
Jan 26, 2022
Updated
May 5, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-190, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 26, 2022CVE publishedPublication date reported by the CVE source.
  2. May 5, 2025Record 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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-190Integer Overflow or Wraparound
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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