CVE-2026-7210

< 2.8.0

xml.parsers.expat and xml.etree.ElementTree use insufficient entropy for Expat hash-flooding protection, which allows a crafte

9.8CRITICAL

CVE-2026-45186

< 2.8.1

In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderatel

2.9LOW

CVE-2026-41080

< 2.7.6

libexpat before 2.8.0 uses insufficient entropy, and thus hash flooding can occur via a crafted XML document.

2.9LOW

CVE-2026-32778

< 2.7.5

libexpat before 2.7.5 allows a NULL pointer dereference in the function setContext on retry after an earlier ouf-of-memory conditi

2.9LOW

CVE-2026-32777

< 2.7.5

libexpat before 2.7.5 allows an infinite loop while parsing DTD content.

4.0MEDIUM

CVE-2026-32776

< 2.7.5

libexpat before 2.7.5 allows a NULL pointer dereference with empty external parameter entity content.

4.0MEDIUM

CVE-2026-25210

< 2.7.4

In libexpat before 2.7.4, the doContent function does not properly determine the buffer size bufSize because there is no integer o

6.9MEDIUM

CVE-2026-24515

< 2.7.4

In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.

2.9LOW

CVE-2025-66382

<= 2.7.3

In libexpat through 2.7.3, a crafted file with an approximate size of 2 MiB can lead to dozens of seconds of processing time.

2.9LOW

CVE-2025-59375

< 2.7.2

libexpat in Expat before 2.7.2 allows attackers to trigger large dynamic memory allocations via a small document that is submitted

7.5HIGH

CVE-2024-50602

< 2.6.4

An issue was discovered in libexpat before 2.6.4. There is a crash within the XML_ResumeParser function because XML_StopParser can

5.9MEDIUM

CVE-2024-45492

< 2.6.3

An issue was discovered in libexpat before 2.6.3. nextScaffoldPart in xmlparse.c can have an integer overflow for m_groupSize on 3

9.8CRITICAL

CVE-2024-45491

< 2.6.3

An issue was discovered in libexpat before 2.6.3. dtdCopy in xmlparse.c can have an integer overflow for nDefaultAtts on 32-bit pl

9.8CRITICAL

CVE-2024-45490

< 2.6.3

An issue was discovered in libexpat before 2.6.3. xmlparse.c does not reject a negative length for XML_ParseBuffer.

7.5HIGH

CVE-2024-28757

< 2.6.2

libexpat through 2.6.1 allows an XML Entity Expansion attack when there is isolated use of external parsers (created via XML_Exter

7.5HIGH

CVE-2023-52426

<= 2.5.0

libexpat through 2.5.0 allows recursive XML Entity Expansion if XML_DTD is undefined at compile time.

5.5MEDIUM

CVE-2023-52425

<= 2.5.0

libexpat through 2.5.0 allows a denial of service (resource consumption) because many full reparsings are required in the case of

7.5HIGH

CVE-2022-43680

<= 2.4.9

In libexpat through 2.4.9, there is a use-after free caused by overeager destruction of a shared DTD in XML_ExternalEntityParserCr

7.5HIGH

CVE-2022-40674

< 2.4.9

libexpat before 2.4.9 has a use-after-free in the doContent function in xmlparse.c.

8.1HIGH

CVE-2022-25315

< 2.4.5

In Expat (aka libexpat) before 2.4.5, there is an integer overflow in storeRawNames.

9.8CRITICAL

CVE-2022-25314

< 2.4.5

In Expat (aka libexpat) before 2.4.5, there is an integer overflow in copyString.

7.5HIGH

CVE-2022-25313

< 2.4.5

In Expat (aka libexpat) before 2.4.5, an attacker can trigger stack exhaustion in build_model via a large nesting depth in the DTD

6.5MEDIUM

CVE-2022-25236

< 2.4.5

xmlparse.c in Expat (aka libexpat) before 2.4.5 allows attackers to insert namespace-separator characters into namespace URIs.

9.8CRITICAL

CVE-2022-25235

< 2.4.5

xmltok_impl.c in Expat (aka libexpat) before 2.4.5 lacks certain validation of encoding, such as checks for whether a UTF-8 charac

9.8CRITICAL

CVE-2022-23990

< 2.4.4

Expat (aka libexpat) before 2.4.4 has an integer overflow in the doProlog function.

7.5HIGH

CVE-2022-23852

< 2.4.4

Expat (aka libexpat) before 2.4.4 has a signed integer overflow in XML_GetBuffer, for configurations with a nonzero XML_CONTEXT_BY

9.8CRITICAL

CVE-2022-22827

< 2.4.3

storeAtts in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.

8.8HIGH

CVE-2022-22826

< 2.4.3

nextScaffoldPart in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.

8.8HIGH

CVE-2022-22825

< 2.4.3

lookup in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.

8.8HIGH

CVE-2022-22824

< 2.4.3

defineAttribute in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.

9.8CRITICAL

CVE-2022-22823

< 2.4.3

build_model in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.

9.8CRITICAL

CVE-2022-22822

< 2.4.3

addBinding in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.

9.8CRITICAL

CVE-2021-46143

< 2.4.3

In doProlog in xmlparse.c in Expat (aka libexpat) before 2.4.3, an integer overflow exists for m_groupSize.

8.1HIGH

CVE-2021-45960

< 2.4.3

In Expat (aka libexpat) before 2.4.3, a left shift by 29 (or more) places in the storeAtts function in xmlparse.c can lead to real

8.8HIGH

CVE-2019-15903

< 2.2.8

In libexpat before 2.2.8, crafted XML input could fool the parser into changing from DTD parsing to document parsing too early; a

7.5HIGH

CVE-2018-20843

< 2.2.7

In libexpat in Expat before 2.2.7, XML input including XML names that contain a large number of colons could make the XML parser c

7.5HIGH

CVE-2017-11742

all versions

The writeRandomBytes_RtlGenRandom function in xmlparse.c in libexpat in Expat 2.2.1 and 2.2.2 on Windows allows local users to gai

7.8HIGH

CVE-2017-9233

<= 2.2.0

XML External Entity vulnerability in libexpat 2.2.0 and earlier (Expat XML Parser Library) allows attackers to put the parser in a

7.5HIGH

CVE-2016-4472

<= 2.1.1

The overflow protection in Expat is removed by compilers with certain optimization settings, which allows remote attackers to caus

8.1HIGH

CVE-2016-5300

< 2.2.0

The XML parser in Expat does not use sufficient entropy for hash initialization, which allows context-dependent attackers to cause

7.5HIGH

CVE-2012-6702

< 2.2.0

Expat, when used in a parser that has not called XML_SetHashSalt or passed it a seed of 0, makes it easier for context-dependent a

5.9MEDIUM

CVE-2016-0718

< 2.2.0

Expat allows context-dependent attackers to cause a denial of service (crash) or possibly execute arbitrary code via a malformed i

9.8CRITICAL

CVE-2015-1283

<= 2.1.0

Multiple integer overflows in the XML_GetBuffer function in Expat through 2.1.0, as used in Google Chrome before 44.0.2403.89 and

CVE-2013-0340

< 2.4.0

expat before version 2.4.0 does not properly handle entities expansion unless an application developer uses the XML_SetEntityDeclH

CVE-2012-1148

<= 2.0.1

Memory leak in the poolGrow function in expat/lib/xmlparse.c in expat before 2.1.0 allows context-dependent attackers to cause a d

CVE-2012-1147

<= 2.0.1

readfilemap.c in expat before 2.1.0 allows context-dependent attackers to cause a denial of service (file descriptor consumption)

CVE-2012-0876

< 2.1.0

The XML parser (xmlparse.c) in expat before 2.1.0 computes hash values without restricting the ability to trigger hash collisions

CVE-2009-3560

all versions

The big2_toUtf8 function in lib/xmltok.c in libexpat in Expat 2.0.1, as used in the XML-Twig module for Perl, allows context-depen

CVE-2009-3720

all versions

The updatePosition function in lib/xmltok_impl.c in libexpat in Expat 2.0.1, as used in Python, PyXML, w3c-libwww, and other softw