Detections
Analytics
EulerOS 2.0 SP11 : expat (EulerOS-SA-2026-4225)
high Nessus Plugin ID 364764
Synopsis
The remote EulerOS host is missing multiple security updates.Description
According to the versions of the expat packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :Expat through 2.8.3 contains an out-of-bounds read vulnerability that allows attackers to trigger memory corruption by processing XML with external entity parsers created via XML_ExternalEntityParserCreate. A struct size mismatch between ELEMENT_TYPE members causes storeAtts to read the attIndex member past allocated memory boundaries, resulting in failure to normalize whitespace in non-CDATA attributes or a wild pointer dereference causing a segfault. This vulnerability was introduced by the fix for CVE-2026-66046.(CVE-2026-76641)
Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementType-defaultAtts to determine CDATA status. A remote unauthenticated attacker can supply a single well-formed XML document of a few megabytes to an application parsing untrusted XML to cause excessive CPU consumption, resulting in denial of service without requiring authentication, external entity resolution, or non-default parser options.(CVE-2026-66046)
libexpat before 2.8.2 does not consider XML_TOK_DATA_CHARS in doCdataSection and thus lacks handler call depth tracking for various calls from within handlers in cases of a policy violation. Thus, a use-after- free can occur. NOTE: this issue exists because of an incomplete fix for CVE-2026-50219.(CVE-2026-56412)
libexpat before 2.8.2 has an integer overflow in copyString.(CVE-2026-56408)
libexpat before 2.8.2 has an integer overflow in getAttributeId.(CVE-2026-56405)
xmlwf in libexpat before 2.8.2 has an integer overflow for the output filename when -d outputDir is used.(CVE-2026-56409)
xmlwf in libexpat before 2.8.2 has an integer overflow in resolveSystemId.(CVE-2026-56410)
libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.(CVE-2026-56406)
xmlwf in libexpat before 2.8.2 has an integer overflow in endDoctypeDecl via NOTATION declarations.(CVE-2026-56411)
libexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen.(CVE-2026-56407)
In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers.(CVE-2026-56132)
libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation. Thus, a use-after-free can occur (similar to the CVE-2026-50219 situation).(CVE-2026-56131)
libexpat before 2.8.2 has an integer overflow in storeAtts.(CVE-2026-56403)
libexpat before 2.8.2 has an integer overflow in addBinding.(CVE-2026-56404)
libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation.
Thus, a use-after-free can occur,(CVE-2026-50219)
Tenable has extracted the preceding description block directly from the EulerOS expat security advisory.
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.
Solution
Update the affected expat packages.See Also
Plugin Details
Severity: High
ID: 364764
File Name: EulerOS_SA-2026-4225.nasl
Version: 1.1
Type: Local
Family: Huawei Local Security Checks
Published: 10/12/2026
Updated: 10/12/2026
Supported Sensors: Nessus
Risk Information
VPR
Risk Factor: Medium
Score: 4.5
Percentile: 57.56
CVSS v2
Risk Factor: Medium
Base Score: 4.6
Temporal Score: 3.6
Vector: CVSS2#AV:L/AC:L/Au:N/C:P/I:P/A:P
CVSS Score Source: CVE-2026-56412
CVSS v3
Risk Factor: Medium
Base Score: 6.9
Temporal Score: 6.2
Vector: CVSS:3.0/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L
Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C
CVSS Score Source: CVE-2026-56405
CVSS v4
Risk Factor: High
Base Score: 8.7
Threat Score: 7.7
Threat Vector: CVSS:4.0/E:P
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS Score Source: CVE-2026-76641
Vulnerability Information
CPE: cpe:/o:huawei:euleros:2.0, p-cpe:/a:huawei:euleros:expat-devel, p-cpe:/a:huawei:euleros:expat-help, p-cpe:/a:huawei:euleros:expat
Required KB Items: Host/local_checks_enabled, Host/cpu, Host/EulerOS/release, Host/EulerOS/rpm-list, Host/EulerOS/sp
Excluded KB Items: Host/EulerOS/uvp_version
Exploit Available: true
Exploit Ease: Exploits are available
Patch Publication Date: 10/10/2026
Vulnerability Publication Date: 6/4/2026
Reference Information
CVE: CVE-2026-50219, CVE-2026-56131, CVE-2026-56132, CVE-2026-56403, CVE-2026-56404, CVE-2026-56405, CVE-2026-56406, CVE-2026-56407, CVE-2026-56408, CVE-2026-56409, CVE-2026-56410, CVE-2026-56411, CVE-2026-56412, CVE-2026-66046, CVE-2026-76641
IAVA: 2026-A-0650-S, 2026-A-0925-S