Loop With Unreachable Exit Condition ('Infinite Loop') SNYK-DEBIAN8-LIBXML2-542925
Introduction
In this article, we will discuss a critical vulnerability in the libxml2
library, specifically the xmlStringLenDecodeEntities
function in parser.c
, which has an infinite loop in a certain end-of-file situation. This vulnerability is identified as SNYK-DEBIAN8-LIBXML2-542925 and affects the libxml2
package in Debian 8.
NVD Description
Note: Versions mentioned in the description apply only to the upstream libxml2
package and not the libxml2
package as distributed by Debian
.
See How to fix?
for Debian:8
relevant fixed versions and status.
The xmlStringLenDecodeEntities
function in parser.c
in libxml2
2.9.10 has an infinite loop in a certain end-of-file situation. This vulnerability can be exploited by an attacker to cause a denial-of-service (DoS) attack.
Remediation
Unfortunately, there is no fixed version for Debian:8
libxml2
. This means that users of libxml2
in Debian 8 are vulnerable to this attack and should take alternative measures to mitigate the risk.
References
- https://security-tracker.debian.org/tracker/CVE-2020-7595
- https://cert-portal.siemens.com/productcert/pdf/ssa-292794.pdf
- https://security.netapp.com/advisory/ntap-20200702-0005/
- https://us-cert.cisa.gov/ics/advisories/icsa-21-103-08
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/5R55ZR52RMBX24TQTWHCIWKJVRV6YAWI/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JDPF3AAVKUAKDYFMFKSIQSVVS3EEFPQH/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/545SPOI3ZPPNPX4TFRIVE4JVRTJRKULL/
- https://security.gentoo.org/glsa/202010-04
- https://gitlab.gnome.org/GNOME/libxml2/commit/0e1a49c89076
- https://www.oracle.com/security-alerts/cpujul2020.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://lists.debian.org/debian-lts-announce/2020/09/msg00009.html
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00047.html
- http://people.ubuntu.com/~ubuntu-security/cve/CVE-2020-7595
- https://usn.ubuntu.com/4274-1/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/545SPOI3ZPPNPX4TFRIVE4JVRTJRKULL/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/5R55ZR52RMBX24TQTWHCIWKJVRV6YAWI/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JDPF3AAVKUAKDYFMFKSIQSVVS3EEFPQH/
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujul2022.html
Mitigation Strategies
While there is no fixed version for Debian:8
libxml2
, there are some mitigation strategies that can be employed to reduce the risk of this vulnerability:
- Disable the vulnerable function: If possible, disable the
xmlStringLenDecodeEntities
function inparser.c
to prevent it from being used. - Use a different library: Consider using a different library that is not vulnerable to this issue.
- Apply a patch: If a patch is available, apply it to the
libxml2
package to fix the vulnerability. - Use a secure configuration: Ensure that the
libxml2
package is configured securely to prevent exploitation of this vulnerability.
Conclusion
Q: What is the vulnerability in the libxml2
library?
A: The xmlStringLenDecodeEntities
function in parser.c
in libxml2
2.9.10 has an infinite loop in a certain end-of-file situation, which can be exploited by an attacker to cause a denial-of-service (DoS) attack.
Q: What is the impact of this vulnerability?
A: This vulnerability can cause a denial-of-service (DoS) attack, which can lead to a system crash or a service disruption.
Q: Is this vulnerability specific to libxml2
?
A: No, this vulnerability is not specific to libxml2
. However, it is a critical vulnerability in the libxml2
library.
Q: What is the affected version of libxml2
?
A: The affected version of libxml2
is 2.9.10.
Q: Is there a fixed version of libxml2
available?
A: Unfortunately, there is no fixed version of libxml2
available for Debian:8
.
Q: What are the mitigation strategies for this vulnerability?
A: The mitigation strategies for this vulnerability include:
- Disable the vulnerable function: If possible, disable the
xmlStringLenDecodeEntities
function inparser.c
to prevent it from being used. - Use a different library: Consider using a different library that is not vulnerable to this issue.
- Apply a patch: If a patch is available, apply it to the
libxml2
package to fix the vulnerability. - Use a secure configuration: Ensure that the
libxml2
package is configured securely to prevent exploitation of this vulnerability.
Q: How can I protect my system from this vulnerability?
A: To protect your system from this vulnerability, follow the mitigation strategies outlined above. Additionally, ensure that your system is up-to-date with the latest security patches and updates.
Q: What are the references for this vulnerability?
A: The references for this vulnerability include:
- https://security-tracker.debian.org/tracker/CVE-2020-7595
- https://cert-portal.siemens.com/productcert/pdf/ssa-292794.pdf
- https://security.netapp.com/advisory/ntap-20200702-0005/
- https://us-cert.cisa.gov/ics/advisories/icsa-21-103-08
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/5R55ZR52RMBX24TQTWHCIWKJVRV6YI/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JDPF3AAVKUAKDYFMFKSIQSVVS3EEFPQH/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/545SPOI3ZPPNPX4TFRIVE4JVRTJRKULL/
- https://security.gentoo.org/glsa/202010-04
- https://gitlab.gnome.org/GNOME/libxml2/commit/0e1a49c89076
- https://www.oracle.com/security-alerts/cpujul2020.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://lists.debian.org/debian-lts-announce/2020/09/msg00009.html
- http://lists.opensuse.org/opensuse-security-announce/2020-05/msg00047.html
- http://people.ubuntu.com/~ubuntu-security/cve/CVE-2020-7595
- https://usn.ubuntu.com/4274-1/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/545SPOI3ZPPNPX4TFRIVE4JVRTJRKULL/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/5R55ZR52RMBX24TQTWHCIWKJVRV6YAWI/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/JDPF3AAVKUAKDYFMFKSIQSVVS3EEFPQH/
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpujul2022.html
Q: Where can I find more information about this vulnerability?
A: You can find more information about this vulnerability on the following websites: