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GHSA-R396-2Q2C-PJHR
Vulnerability from github – Published: 2026-05-10 09:31 – Updated: 2026-07-14 15:31
VLAI
Details
In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
Severity
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CVE-2026-45186 (GCVE-0-2026-45186)
Vulnerability from cvelistv5 – Published: 2026-05-10 06:36 – Updated: 2026-07-15 00:52
VLAI
EPSS
VEX
Summary
In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
Severity
7.5 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
- CWE-407 - Inefficient Algorithmic Complexity
Assigner
References
12 references
| URL | Tags |
|---|---|
| https://github.com/libexpat/libexpat/pull/1216 | |
| http://www.openwall.com/lists/oss-security/2026/0… | |
| https://access.redhat.com/security/cve/CVE-2026-45186 | vdb-entryx_refsource_REDHAT |
| https://bugzilla.redhat.com/show_bug.cgi?id=2468575 | issue-trackingx_refsource_REDHAT |
| https://security.access.redhat.com/data/csaf/v2/v… | x_sadp-csaf-vex |
| https://access.redhat.com/errata/RHSA-2026:22715 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:23230 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:22721 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:29197 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:27201 | vendor-advisoryx_refsource_REDHAT |
| https://access.redhat.com/errata/RHSA-2026:26319 | vendor-advisoryx_refsource_REDHAT |
| https://cert-portal.siemens.com/productcert/html/… |
Impacted products
17 products
| Vendor | Product | Version | |
|---|---|---|---|
| libexpat project | libexpat |
Affected:
0 , < 2.8.1
(semver)
|
|
| Red Hat | Red Hat Enterprise Linux 10 |
Unaffected:
0:2.7.3-1.el10_2.1 , < *
(rpm)
cpe:/o:redhat:enterprise_linux:10.2 |
|
| Red Hat | Red Hat Enterprise Linux 8 |
Unaffected:
0:2.5.0-2.el8_10 , < *
(rpm)
cpe:/o:redhat:enterprise_linux:8 |
|
| Red Hat | Red Hat Enterprise Linux 9 |
Unaffected:
0:2.5.0-6.el9_8.1 , < *
(rpm)
cpe:/a:redhat:enterprise_linux:9 cpe:/o:redhat:enterprise_linux:9 |
|
| Red Hat | Red Hat JBoss Core Services 2.4.62.SP4 |
cpe:/a:redhat:jboss_core_services:1 |
|
| Red Hat | Red Hat Discovery 2 |
Unaffected:
1782159791 , < *
(rpm)
cpe:/a:redhat:discovery:2::el9 |
|
| Red Hat | Red Hat Discovery 2 |
Unaffected:
1782166952 , < *
(rpm)
cpe:/a:redhat:discovery:2::el9 |
|
| Red Hat | Red Hat Update Infrastructure 5 |
Unaffected:
1781525684 , < *
(rpm)
cpe:/a:redhat:rhui:5::el9 |
|
| Red Hat | Red Hat Update Infrastructure 5 |
Unaffected:
1781525671 , < *
(rpm)
cpe:/a:redhat:rhui:5::el9 |
|
| Red Hat | Red Hat Update Infrastructure 5 |
Unaffected:
1781525693 , < *
(rpm)
cpe:/a:redhat:rhui:5::el9 |
|
| Red Hat | Red Hat Update Infrastructure 5 |
Unaffected:
1781525739 , < *
(rpm)
cpe:/a:redhat:rhui:5::el9 |
|
| Red Hat | Red Hat Enterprise Linux 6 |
cpe:/o:redhat:enterprise_linux:6 |
|
| Red Hat | Red Hat Enterprise Linux 7 |
cpe:/o:redhat:enterprise_linux:7 |
|
| Red Hat | Red Hat Enterprise Linux 8 |
cpe:/o:redhat:enterprise_linux:8 |
|
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.5 , < V3.1.6
(custom)
|
|
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP |
Affected:
V3.1.5 , < V3.1.6
(custom)
|
|
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP |
Affected:
V3.1.5 , < V3.1.6
(custom)
|
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"dataVersion": "5.2"
}
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Trend slope:
-
(linear fit over daily sighting counts)
Show additional events:
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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