The version of libxml2 installed on the remote host is prior to 2.9.1-6.6.42. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS-2023-1743 advisory.

  - parser.c in libxml2 before 2.9.5 mishandles parameter-entity references because the NEXTL macro calls the     xmlParserHandlePEReference function in the case of a '%' character in a DTD name. (CVE-2017-16931)

  - GNOME project libxml2 v2.9.10 has a global buffer over-read vulnerability in xmlEncodeEntitiesInternal at     libxml2/entities.c. The issue has been fixed in commit 50f06b3e. (CVE-2020-24977)

  - There's a flaw in libxml2's xmllint in versions before 2.9.11. An attacker who is able to submit a crafted     file to be processed by xmllint could trigger a use-after-free. The greatest impact of this flaw is to     confidentiality, integrity, and availability. (CVE-2021-3516)

  - There is a flaw in the xml entity encoding functionality of libxml2 in versions before 2.9.11. An attacker     who is able to supply a crafted file to be processed by an application linked with the affected     functionality of libxml2 could trigger an out-of-bounds read. The most likely impact of this flaw is to     application availability, with some potential impact to confidentiality and integrity if an attacker is     able to use memory information to further exploit the application. (CVE-2021-3517)

  - There's a flaw in libxml2 in versions before 2.9.11. An attacker who is able to submit a crafted file to     be processed by an application linked with libxml2 could trigger a use-after-free. The greatest impact     from this flaw is to confidentiality, integrity, and availability. (CVE-2021-3518)

  - A vulnerability found in libxml2 in versions before 2.9.11 shows that it did not propagate errors while     parsing XML mixed content, causing a NULL dereference. If an untrusted XML document was parsed in recovery     mode and post-validated, the flaw could be used to crash the application. The highest threat from this     vulnerability is to system availability. (CVE-2021-3537)

  - A flaw was found in libxml2. Exponential entity expansion attack its possible bypassing all existing     protection mechanisms and leading to denial of service. (CVE-2021-3541)

  - valid.c in libxml2 before 2.9.13 has a use-after-free of ID and IDREF attributes. (CVE-2022-23308)

  - In libxml2 before 2.9.14, several buffer handling functions in buf.c (xmlBuf*) and tree.c (xmlBuffer*)     don't check for integer overflows. This can result in out-of-bounds memory writes. Exploitation requires a     victim to open a crafted, multi-gigabyte XML file. Other software using libxml2's buffer functions, for     example libxslt through 1.1.35, is affected as well. (CVE-2022-29824)

  - An issue was discovered in libxml2 before 2.10.3. When parsing a multi-gigabyte XML document with the     XML_PARSE_HUGE parser option enabled, several integer counters can overflow. This results in an attempt to     access an array at a negative 2GB offset, typically leading to a segmentation fault. (CVE-2022-40303)

  - An issue was discovered in libxml2 before 2.10.3. Certain invalid XML entity definitions can corrupt a     hash table key, potentially leading to subsequent logic errors. In one case, a double-free can be     provoked. (CVE-2022-40304)

  - In libxml2 before 2.10.4, parsing of certain invalid XSD schemas can lead to a NULL pointer dereference     and subsequently a segfault. This occurs in xmlSchemaFixupComplexType in xmlschemas.c. (CVE-2023-28484)

  - An issue was discovered in libxml2 before 2.10.4. When hashing empty dict strings in a crafted XML     document, xmlDictComputeFastKey in dict.c can produce non-deterministic values, leading to various logic     and memory errors, such as a double free. This behavior occurs because there is an attempt to use the     first byte of an empty string, and any value is possible (not solely the '\0' value). (CVE-2023-29469)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Detections

Analytics

Amazon Linux AMI : libxml2 (ALAS-2023-1743)

critical Nessus Plugin ID 175091

Version 1.1

Version 1.0

Version 1.1 May 5, 2023, 2:01 PM Exploit attributes ("Exploitability ease" changed from "No known exploits are available" to "Exploits are available") Plugin Feed: 202305051401
Version 1.0 May 4, 2023, 2:03 PM New Plugin Feed: 202305041403