CVE-2025-59375Network attack vector

Denial of service via allocation amplification

Published Sep 15, 2025 · Updated Jul 14, 2026

Resource exhaustion in Expat libexpat before 2.7.2 allows remote attackers to crash parsing processes with a small XML document. Each opening XML tag causes a fixed-size TAG structure and buffer allocation, allowing roughly 250 KiB of input to consume about 800 MiB of heap. Exploitation requires a consuming application to parse attacker-controlled XML; the consequence is process termination or service interruption from memory exhaustion.

CVSS severity7.5
High
EPSS probability1.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Resource exhaustion in Expat libexpat before 2.7.2 allows remote attackers to crash parsing processes with a small XML document. Each opening XML tag causes a fixed-size TAG structure and buffer allocation, allowing roughly 250 KiB of input to consume about 800 MiB of heap. Exploitation requires a consuming application to parse attacker-controlled XML; the consequence is process termination or service interruption from memory exhaustion.

The record

CVE
CVE-2025-59375
Published
Sep 15, 2025
Updated
Jul 14, 2026
Vendor
Siemens
Product
SCALANCE XRM334 (24 V DC, 12xFO)
Classifications
CWE-770, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 15, 2025CVE publishedPublication date reported by the CVE source.
  2. Jul 14, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=0 <V3.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Siemens · SCALANCE XRM334 (24 V DC, 12xFO)version=0 <V3.3
Siemens · SIPLUS S7-1500 CPU 1518-4 PN/DP MFPversion=V3.1.5 <*
Siemens · SCALANCE XCM324version=0 <V3.3
Siemens · SCALANCE XRM334 (230 V AC, 12xFO)version=0 <V3.3
Siemens · SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 familyversion=0 <V3.3
Expat Project · libexpatversion=0 <2.7.2
Siemens · SCALANCE XCM332version=0 <V3.3
Siemens · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFPversion=V3.1.5 <*
Siemens · SCALANCE XCM328version=0 <V3.3
Siemens · SCALANCE XRM334 (2x230 V AC, 12xFO)version=0 <V3.3
Siemens · SCALANCE XRM334 (24 V DC, 8xFO)version=0 <V3.3
Siemens · SCALANCE XRM334 (24V DC, 2x10G, 24xSFP, 8xSFP+)version=0 <V3.3
Siemens · SCALANCE XRM334 (230V AC, 2x10G, 24xSFP, 8xSFP+)version=0 <V3.3
Siemens · SCALANCE XRM334 (2x230 V AC, 8xFO)version=0 <V3.3
Siemens · RUGGEDCOM RST2428Pversion=0 <V3.3
Siemens · SCALANCE XRM334 (230 V AC, 8xFO)version=0 <V3.3
Siemens · SCALANCE XRM334 (2x230V AC, 2x10G, 24xSFP, 8xSFP+)version=0 <V3.3
Siemens · SCALANCE XCH328version=0 <V3.3
Siemens · SCALANCE XRH334 (24 V DC, 8xFO, CC)version=0 <V3.3
Siemens · SIMATIC S7-1500 CPU 1518-4 PN/DP MFPversion=V3.1.5 <*

Published CVSS scores

7.2Expat ProjectCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:H/RL:O/RC:C
7.5Expat ProjectCVSS: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.

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

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-770Allocation of Resources Without Limits or Throttling
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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo