Where
-Infinity
0
Severity
9.8
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An issue was discovered in libexpat before 2.6.3. dtdCopy in xmlparse.c can have an integer overflow for nDefaultAtts on 32-bit platforms (where UINTMAX equals SIZEMAX).

1 / 3
Source: MITRE
First published (updated )
Severity
9.8
Input Validation, Race Condition, Use After Free, XEE, Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Accounts. A logic issue was addressed with improved file handling.

1 / 39
Source: Apple
First published (updated )
Severity
9.8
Integer Overflow, Buffer Overflow, Use After Free
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An issue was discovered in libexpat before 2.6.3. nextScaffoldPart in xmlparse.c can have an integer overflow for mgroupSize on 32-bit platforms (where UINTMAX equals SIZEMAX).

1 / 3
Source: MITRE
First published (updated )
Severity
9.8
Buffer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An out-of-bounds read flaw was found in the way Expat processed certain input. A remote attacker could send specially crafted XML that, when parsed by an application using the Expat library, would cause that application to crash or, possibly, execute arbitrary code with the permission of the user running the application.

1 / 4
First published (updated )
Severity
9.8
Input Validation
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

A flaw was found in expat. Passing malformed 2- and 3-byte UTF-8 sequences (for example, from start tag names) to the XML processing application on top of expat can lead to arbitrary code execution. This issue is dependent on how invalid UTF-8 is handled inside the XML processor.

1 / 5
First published (updated )
Severity
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

A flaw was found in expat. Passing one or more namespace separator characters in the "xmlns[:prefix]" attribute values made expat send malformed tag names to the XML processor on top of expat. This issue causes arbitrary code execution depending on how unexpected cases are handled inside the XML processor.

1 / 4
First published (updated )
Severity
9.8
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An integer overflow was found in expat. The issue occurs in storeRawNames() by abusing the mbuffer expansion logic to allow allocations very close to INTMAX and out-of-bounds heap writes. This flaw can cause a denial of service or potentially arbitrary code execution.

1 / 3
First published (updated )
Severity
9.8
Integer Overflow
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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

1 / 5
First published (updated )
Severity
9.8
Integer Overflow
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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

1 / 5
First published (updated )
Severity
9.8
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Expat (aka libexpat) before 2.4.4 has a signed integer overflow in XMLGetBuffer, for configurations with a nonzero XMLCONTEXTBYTES.

1 / 5
First published (updated )
Severity
9.8
Integer Overflow
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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

1 / 4
First published (updated )
Severity
8.8
Use After Free
AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

A flaw in XML parsing could have led to a use-after-free causing a potentially exploitable crash.In official releases of Firefox this vulnerability is mitigated by wasm sandboxing; versions managed by Linux distributions may have other settings.

1 / 5
First published (updated )
Severity
8.8
Buffer Overflow
AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Expat (aka libexpat) is vulnerable to a denial of service, caused by a realloc misbehavior issue in the storeAtts function in xmlparse.c. By persuading a victim to open a specially-crafted XML content, a remote attacker could exploit this vulnerability to cause a the application to crash.

1 / 5
Source: IBM
First published (updated )
Severity
8.8
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

expat (libexpat) is susceptible to a software flaw that causes process interruption. When processing a large number of prefixed XML attributes on a single tag can libexpat can terminate unexpectedly due to integer overflow. The highest threat from this vulnerability is to availability, confidentiality and integrity.

1 / 5
First published (updated )
Severity
8.8
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

expat (libexpat) is susceptible to a software flaw that causes process interruption. When processing a large number of prefixed XML attributes on a single tag can libexpat can terminate unexpectedly due to integer overflow. The highest threat from this vulnerability is to availability, confidentiality and integrity.

1 / 5
First published (updated )
Severity
8.8
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

expat (libexpat) is susceptible to a software flaw that causes process interruption. When processing a large number of prefixed XML attributes on a single tag can libexpat can terminate unexpectedly due to integer overflow. The highest threat from this vulnerability is to availability, confidentiality and integrity.

1 / 5
First published (updated )
Severity
8.1
Integer Overflow
AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

expat (libexpat) is susceptible to a software flaw that causes process interruption. When processing a large number of prefixed XML attributes on a single tag can libexpat can terminate unexpectedly due to integer overflow. The highest threat from this vulnerability is to availability, confidentiality and integrity.

1 / 4
First published (updated )
Severity
7.8
EPSS
0.01%
Integer Overflow
AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L

In libexpat before 2.7.4, the doContent function does not properly determine the buffer size bufSize because there is no integer overflow check for tag buffer reallocation.

First published (updated )
Severity
7.8
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Last updated 24 July 2024

1 / 2
Source: Ubuntu
First published (updated )
Severity
7.8
XEE
AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

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 consume a high amount of RAM and CPU resources while processing (enough to be usable for denial-of-service attacks).

1 / 5
First published (updated )
Severity
7.8
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

The writeRandomBytesRtlGenRandom function in xmlparse.c in libexpat in Expat 2.2.1 and 2.2.2 on Windows allows local users to gain privileges via a Trojan horse ADVAPI32.DLL in the current working directory because of an untrusted search path, aka DLL hijacking.

First published (updated )
Severity
7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

libexpat is vulnerable to a denial of service, caused by improper system resource allocation. By sending a specially crafted request using an overly large token, a remote attacker could exploit this vulnerability to cause a denial of service.

1 / 4
Source: IBM
First published (updated )
Severity
7.5
EPSS
0.04%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

libexpat could allow a remote attacker to obtain sensitive information, caused by improper handling of XML external entity (XXE) declarations by the XMLExternalEntityParserCreate function. By using a specially crafted XML content, a remote attacker could exploit this vulnerability to obtain sensitive information, and use this information to launch further attacks against the affected system.

1 / 4
Source: IBM
First published (updated )
Severity
7.5
Use After Free
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A use-after-free flaw was found in the Expat package, caused by destruction of a shared DTD in XMLExternalEntityParserCreate in out-of-memory situations. This may lead to availability disruptions.

1 / 5
First published (updated )
Severity
7.5
Use After Free, Race Condition, Input Validation, Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Accessibility. A privacy issue was addressed by removing sensitive data.

1 / 40
Source: Apple
First published (updated )
Severity
7.5
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

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

First published (updated )
Severity
7.5
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

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.

First published (updated )
Severity
7.5
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

An integer overflow flaw was found in expat. This issue affects the encoding name parameter at the parser creation time, which is often hard-coded (rather than user input), takes a value in the gigabytes to trigger, and on a 64-bit machine. This flaw can cause a denial of service.

1 / 3
First published (updated )
Severity
7.5
Integer Overflow
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

A flaw was found in expat. The vulnerability occurs due to large content in element type declarations when there is an element declaration handler present which leads to an integer overflow. This flaw allows an attacker to inject an unsigned integer, leading to a crash or a denial of service.

1 / 5
First published (updated )
Severity
7.5
XEE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

libexpat. Multiple issues were addressed by updating to version 2.2.1

1 / 2
First published (updated )

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