CVE-2021-3518
published 2021-05-18CVE-2021-3518: 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…
PriorityP261high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
21.86%
97.6th percentile
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.
Affected
34 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| 3scale-amp2 | backend-rhel8 | — | — |
| 3scale-amp2 | system-rhel8 | — | — |
| 3scale-amp2 | system-rhel9 | — | — |
| 3scale-amp2 | toolbox-rhel9 | — | — |
| 3scale-amp2 | zync-rhel9 | — | — |
| apple | ios_14.7_and_ipados | — | — |
| debian | debian_linux | — | — |
| debian | libxml2 | < libxml2 2.9.10+dfsg-6.6 (bookworm) | libxml2 2.9.10+dfsg-6.6 (bookworm) |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| msrc | cm1_libxml2_2.9.12-1_on_cbl_mariner_1.0 | — | — |
| nokogiri | nokogiri | < 1.11.4 | 1.11.4 |
| nokogiri | nokogiri | >= 0 < 1.11.4 | 1.11.4 |
| oracle | communications_cloud_native_core_network_function_cloud_native_environment | — | — |
| oracle | enterprise_manager_base_platform | — | — |
| oracle | enterprise_manager_base_platform | — | — |
| oracle | enterprise_manager_ops_center | — | — |
| oracle | mysql_workbench | <= 8.0.26 | — |
| oracle | peoplesoft_enterprise_peopletools | — | — |
| oracle | real_user_experience_insight | — | — |
| oracle | real_user_experience_insight | — | — |
| paloalto | pan-os | — | — |
| redhat | enterprise_linux | — | — |
| satellite_el8 | rubygem-nokogiri | — | — |
| xmlsoft | libxml2 | < 2.9.11 | 2.9.11 |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
ghsa7.5HIGH
osv9.1CRITICAL
vendor_ubuntu9.1CRITICAL
vendor_debian8.8HIGH
vendor_msrc8.8HIGH
vendor_oracle8.8HIGH
vendor_redhat8.8HIGH
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GHSA
Nokogiri before 1.11.4 (CRuby implementation only, when the packaged/vendored libxml2 is used) bundles libxml2 2.9.10, which is affected by multiple vulnerabilities addressed in libxml2 2.9.12, includ
ghsa_unreviewed·2026-08-25·CVSS 7.5
CVE-2021-47996 [HIGH] CWE-119 Nokogiri before 1.11.4 (CRuby implementation only, when the packaged/vendored libxml2 is used) bundles libxml2 2.9.10, which is affected by multiple vulnerabilities addressed in libxml2 2.9.12, includ
Nokogiri before 1.11.4 (CRuby implementation only, when the packaged/vendored libxml2 is used) bundles libxml2 2.9.10, which is affected by multiple vulnerabilities addressed in libxml2 2.9.12, including a memory leak in xmlSchemaValidateStream (CVE-2019-20388), a global buffer over-read in xmlEncodeEntitiesInternal (CVE-2020-24977), a heap-based buffer overflow (CVE-2021-3517), and an out-of-bounds read (CVE-2021-3518). Processing crafted XML documents may lead to denial of service, information disclosure, or memory corruption.
GHSA
Nokogiri Implements libxml2 version vulnerable to use-after-free
ghsa·2022-05-24
CVE-2021-3518 [HIGH] CWE-416 Nokogiri Implements libxml2 version vulnerable to use-after-free
Nokogiri Implements libxml2 version vulnerable to use-after-free
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.
OSV
Nokogiri Implements libxml2 version vulnerable to use-after-free
osv·2022-05-24
CVE-2021-3518 [HIGH] Nokogiri Implements libxml2 version vulnerable to use-after-free
Nokogiri Implements libxml2 version vulnerable to use-after-free
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.
OSV
libxml2 vulnerabilities
osv·2021-06-17·CVSS 9.1
CVE-2017-8872 [CRITICAL] libxml2 vulnerabilities
libxml2 vulnerabilities
Yunho Kim discovered that libxml2 incorrectly handled certain error
conditions. A remote attacker could exploit this with a crafted XML file to
cause a denial of service, or possibly cause libxml2 to expose sensitive
information. This issue only affected Ubuntu 14.04 ESM, and Ubuntu 16.04
ESM. (CVE-2017-8872)
Zhipeng Xie discovered that libxml2 incorrectly handled certain XML
schemas. A remote attacker could possibly use this issue to cause a denial
of service. This issue only affected Ubuntu 14.04 ESM, Ubuntu 16.04 ESM,
and Ubuntu 18.04 LTS. (CVE-2019-20388)
It was discovered that libxml2 incorrectly handled invalid UTF-8 input. A
remote attacker could possibly exploit this with a crafted XML file to
cause libxml2 to crash, resulting in a denial of service. This
OSV
CVE-2021-3518: There's a flaw in libxml2 in versions before 2
osv·2021-05-18·CVSS 8.8
CVE-2021-3518 [HIGH] CVE-2021-3518: There's a flaw in libxml2 in versions before 2
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.
OSV
Nokogiri updates packaged dependency on libxml2 from 2.9.10 to 2.9.12
osv·2021-05-17·CVSS 7.5
CVE-2019-20388 [HIGH] Nokogiri updates packaged dependency on libxml2 from 2.9.10 to 2.9.12
Nokogiri updates packaged dependency on libxml2 from 2.9.10 to 2.9.12
### Summary
Nokogiri v1.11.4 updates the vendored libxml2 from v2.9.10 to v2.9.12 which addresses:
- [CVE-2019-20388](https://security.archlinux.org/CVE-2019-20388) (Medium severity)
- [CVE-2020-24977](https://security.archlinux.org/CVE-2020-24977) (Medium severity)
- [CVE-2021-3517](https://security.archlinux.org/CVE-2021-3517) (Medium severity)
- [CVE-2021-3518](https://security.archlinux.org/CVE-2021-3518) (Medium severity)
- [CVE-2021-3537](https://security.archlinux.org/CVE-2021-3537) (Low severity)
- [CVE-2021-3541](https://security.archlinux.org/CVE-2021-3541) (Low severity)
Note that two additional CVEs were addressed upstream but are not relevant to this release. [CVE-2021-3516](https://security.archlinux.or
GHSA
Nokogiri updates packaged dependency on libxml2 from 2.9.10 to 2.9.12
ghsa·2021-05-17·CVSS 7.5
CVE-2019-20388 [HIGH] Nokogiri updates packaged dependency on libxml2 from 2.9.10 to 2.9.12
Nokogiri updates packaged dependency on libxml2 from 2.9.10 to 2.9.12
### Summary
Nokogiri v1.11.4 updates the vendored libxml2 from v2.9.10 to v2.9.12 which addresses:
- [CVE-2019-20388](https://security.archlinux.org/CVE-2019-20388) (Medium severity)
- [CVE-2020-24977](https://security.archlinux.org/CVE-2020-24977) (Medium severity)
- [CVE-2021-3517](https://security.archlinux.org/CVE-2021-3517) (Medium severity)
- [CVE-2021-3518](https://security.archlinux.org/CVE-2021-3518) (Medium severity)
- [CVE-2021-3537](https://security.archlinux.org/CVE-2021-3537) (Low severity)
- [CVE-2021-3541](https://security.archlinux.org/CVE-2021-3541) (Low severity)
Note that two additional CVEs were addressed upstream but are not relevant to this release. [CVE-2021-3516](https://security.archlinux.or
Red Hat
nokogiri: libxml2: Nokogiri: Memory Corruption via Crafted XML Documents
vendor_redhat·2026-08-25·CVSS 7.5
CVE-2021-47996 [HIGH] CWE-125 nokogiri: libxml2: Nokogiri: Memory Corruption via Crafted XML Documents
nokogiri: libxml2: Nokogiri: Memory Corruption via Crafted XML Documents
Nokogiri before 1.11.4 (CRuby implementation only, when the packaged/vendored libxml2 is used) bundles libxml2 2.9.10, which is affected by multiple vulnerabilities addressed in libxml2 2.9.12, including a memory leak in xmlSchemaValidateStream (CVE-2019-20388), a global buffer over-read in xmlEncodeEntitiesInternal (CVE-2020-24977), a heap-based buffer overflow (CVE-2021-3517), and an out-of-bounds read (CVE-2021-3518). Processing crafted XML documents may lead to denial of service, information disclosure, or memory corruption.
A flaw was found in Nokogiri, specifically within its bundled libxml2 library. A remote attacker could exploit multiple vulnerabilities, including memory leaks, buffer over-reads, heap-based
Palo Alto
PAN-SA-2024-0012 Informational Bulletin: OSS CVEs fixed in PAN-OS
vendor_paloalto·2024-10-29·CVSS 9.8
CVE-2019-17006 [CRITICAL] PAN-SA-2024-0012 Informational Bulletin: OSS CVEs fixed in PAN-OS
PAN-SA-2024-0012 Informational Bulletin: OSS CVEs fixed in PAN-OS
The Palo Alto Networks Product Security Assurance team has evaluated the following open source software (OSS) CVEs as they relate to PAN-OS. While it was not determined that these CVEs have any significant impact on PAN-OS, they have been fixed out of an abundance of caution. CVE Summary CVE-2019-17006 This CVE is fixed in PAN-OS 10.2.0, and all later versions of PAN-OS. CVE-2021-3518 This CVE is fixed in PAN-OS 10.2.0, and all later versions of PAN-OS. CVE-2021-25219 This CVE is fixed in PAN-OS 10.2.3, and all later versions of PAN-OS. CVE-2021-27645 This CVE is fixed in PAN-OS 10.2.8, PAN-OS 11.0.2, and all later versions of PAN-OS. CVE-2021-34798 This CVE is fixed in PAN-OS 10.2.8, PAN-OS 11.0.2, and all later versions o
CISA ICS
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
cisa_ics·2023-12-14
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
ICS Advisory
##
Siemens SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
Release DateDecember 14, 2023
Alert CodeICSA-23-348-10
As of January 10, 2023, CISA will no longer be updating ICS security advisories for Siemens product vulnerabilities beyond the initial advisory. For the most up-to-date information on vulnerabilities in this advisory, please see Siemens' ProductCERT Security Advisories (CERT Services | Services | Siemens Global).
View CSAF
## 1. EXECUTIVE SUMMARY
- CVSS v3 9.8
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: Siemens
- Equipment: SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP V3.1
- Vulnerabilities: Improper Restriction of XML External Entity Reference, Time-of-check Time-of-use (TOCTOU) Race Condition, Command Injection, Miss
Oracle
Oracle Oracle Communications Risk Matrix: OC-CNE (libxml2) — CVE-2021-3518
vendor_oracle·2022-04-15·CVSS 8.8
CVE-2021-3518 [HIGH] Oracle Oracle Communications Risk Matrix: OC-CNE (libxml2) — CVE-2021-3518
Oracle Oracle Communications Risk Matrix: OC-CNE (libxml2) vulnerability
CVE: CVE-2021-3518
CVSS: 8.8
Protocol: HTTP
Remote exploit: Yes
Affected versions: Network
Advisory: cpuapr2022 (APR 2022)
CISA ICS
Hitachi Energy APM Edge (Update A)
cisa_ics·2021-12-02·CVSS 9.1
[CRITICAL] Hitachi Energy APM Edge (Update A)
## Archived Content In an effort to keep CISA.gov current, the archive contains outdated information that may not reflect current policy or programs.
ICS Advisory
##
Hitachi Energy APM Edge (Update A)
Last RevisedOctober 18, 2022
Alert CodeICSA-21-336-06
## 1. EXECUTIVE SUMMARY
- CVSS v3 8.2
- ATTENTION: Low attack complexity
- Vendor: Hitachi Energy
- Equipment: Transformer Asset Performance Management (APM) Edge
- Vulnerability: Reliance on Uncontrolled Component
## 2. UPDATE OR REPOSTED INFORMATION
This updated advisory is a follow-up to the original advisory titled “ICSA-21-336-06 Hitachi Energy APM Edge” that was published December 02, 2021, on the ICS webpage on cisa.gov/ics.
## 3. RISK EVALUATION
Successful exploitation of thi
Oracle
Oracle Oracle Enterprise Manager Risk Matrix: Guest Management (libxml2) — CVE-2021-3518
vendor_oracle·2021-10-15·CVSS 8.8
CVE-2021-3518 [HIGH] Oracle Oracle Enterprise Manager Risk Matrix: Guest Management (libxml2) — CVE-2021-3518
Oracle Oracle Enterprise Manager Risk Matrix: Guest Management (libxml2) vulnerability
CVE: CVE-2021-3518
CVSS: 8.8
Protocol: HTTP
Remote exploit: Yes
Affected versions: Network
Advisory: cpuoct2021 (OCT 2021)
Ubuntu
libxml2 vulnerabilities
vendor_ubuntu·2021-06-17·CVSS 9.1
CVE-2021-3516 [CRITICAL] libxml2 vulnerabilities
Title: libxml2 vulnerabilities
Summary: Several security issues were fixed in libxml2.
Yunho Kim discovered that libxml2 incorrectly handled certain error
conditions. A remote attacker could exploit this with a crafted XML file to
cause a denial of service, or possibly cause libxml2 to expose sensitive
information. This issue only affected Ubuntu 14.04 ESM, and Ubuntu 16.04
ESM. (CVE-2017-8872)
Zhipeng Xie discovered that libxml2 incorrectly handled certain XML
schemas. A remote attacker could possibly use this issue to cause a denial
of service. This issue only affected Ubuntu 14.04 ESM, Ubuntu 16.04 ESM,
and Ubuntu 18.04 LTS. (CVE-2019-20388)
It was discovered that libxml2 incorrectly handled invalid UTF-8 input. A
remote attacker could possibly exploit this with a crafted XML file t
Microsoft
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
vendor_msrc·2021-05-11·CVSS 8.8
CVE-2021-3518 [HIGH] CWE-416 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
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.
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more informa
Red Hat
libxml2: Use-after-free in xmlXIncludeDoProcess() in xinclude.c
vendor_redhat·2021-04-22·CVSS 8.8
CVE-2021-3518 [HIGH] CWE-416 libxml2: Use-after-free in xmlXIncludeDoProcess() in xinclude.c
libxml2: Use-after-free in xmlXIncludeDoProcess() in xinclude.c
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.
There's a flaw in libxml2. 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.
Statement: This flaw is out of support scope for Red Hat Enterprise Linux 6 and 7. To learn more about Red Hat Enterprise Linux support life cycles, please see https://access.redhat.com/support/policy/updates/
Debian
CVE-2021-3518: libxml2 - There's a flaw in libxml2 in versions before 2.9.11. An attacker who is able to ...
vendor_debian·2021·CVSS 8.8
CVE-2021-3518 [HIGH] CVE-2021-3518: libxml2 - There's a flaw in libxml2 in versions before 2.9.11. An attacker who is able to ...
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.
Scope: local
bookworm: resolved (fixed in 2.9.10+dfsg-6.6)
bullseye: resolved (fixed in 2.9.10+dfsg-6.6)
forky: resolved (fixed in 2.9.10+dfsg-6.6)
sid: resolved (fixed in 2.9.10+dfsg-6.6)
trixie: resolved (fixed in 2.9.10+dfsg-6.6)
Apple
CVE-2021-3518: iOS 14.7 and iPadOS 14.7
vendor_apple·CVSS 8.8
CVE-2021-3518 [HIGH] CVE-2021-3518: iOS 14.7 and iPadOS 14.7
Apple Security Update: About the security content of iOS 14.7 and iPadOS 14.7
Product: iOS 14.7 and iPadOS
Version: 14.7
CVE: CVE-2021-3518
Component: CVE-2021-3518
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2021-47996 nokogiri: libxml2: Nokogiri: Memory Corruption via Crafted XML Documents
bugzilla·2026-08-25·CVSS 7.5
CVE-2021-47996 [HIGH] CVE-2021-47996 nokogiri: libxml2: Nokogiri: Memory Corruption via Crafted XML Documents
CVE-2021-47996 nokogiri: libxml2: Nokogiri: Memory Corruption via Crafted XML Documents
Nokogiri before 1.11.4 (CRuby implementation only, when the packaged/vendored libxml2 is used) bundles libxml2 2.9.10, which is affected by multiple vulnerabilities addressed in libxml2 2.9.12, including a memory leak in xmlSchemaValidateStream (CVE-2019-20388), a global buffer over-read in xmlEncodeEntitiesInternal (CVE-2020-24977), a heap-based buffer overflow (CVE-2021-3517), and an out-of-bounds read (CVE-2021-3518). Processing crafted XML documents may lead to denial of service, information disclosure, or memory corruption.
Bugzilla
CVE-2021-3518 libxml2: Use-after-free in xmlXIncludeDoProcess() in xinclude.c
bugzilla·2021-04-27·CVSS 8.8
CVE-2021-3518 [HIGH] CVE-2021-3518 libxml2: Use-after-free in xmlXIncludeDoProcess() in xinclude.c
CVE-2021-3518 libxml2: Use-after-free in xmlXIncludeDoProcess() in xinclude.c
An use-after-free was found in libxml2 in xmlXIncludeDoProcess() in xinclude.c when processing crafted files.
Reference:
https://gitlab.gnome.org/GNOME/libxml2/-/issues/237
Upstream patch:
https://gitlab.gnome.org/GNOME/libxml2/-/commit/1098c30a040e72a4654968547f415be4e4c40fe7
Discussion:
Created libxml2 tracking bugs for this issue:
Affects: fedora-all [bug 1954243]
Created mingw-libxml2 tracking bugs for this issue:
Affects: fedora-all [bug 1954244]
---
Acknowledgments:
Name: zodf0055980 (SQLab NCTU Taiwan)
---
Statement:
This flaw is out of support scope for Red Hat Enterprise Linux 6 and 7. To learn more about Red Hat Enterprise Linux support life cycles, please see https://access.redhat.com/su
http://seclists.org/fulldisclosure/2021/Jul/54http://seclists.org/fulldisclosure/2021/Jul/55http://seclists.org/fulldisclosure/2021/Jul/58http://seclists.org/fulldisclosure/2021/Jul/59https://bugzilla.redhat.com/show_bug.cgi?id=1954242https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3Ehttps://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3Ehttps://lists.debian.org/debian-lts-announce/2021/05/msg00008.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BZOMV5J4PMZAORVT64BKLV6YIZAFDGX6/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QVM4UJ3376I6ZVOYMHBNX4GY3NIV52WV/https://security.gentoo.org/glsa/202107-05https://security.netapp.com/advisory/ntap-20210625-0002/https://support.apple.com/kb/HT212601https://support.apple.com/kb/HT212602https://support.apple.com/kb/HT212604https://support.apple.com/kb/HT212605https://www.oracle.com/security-alerts/cpuapr2022.htmlhttps://www.oracle.com/security-alerts/cpujul2022.htmlhttps://www.oracle.com/security-alerts/cpuoct2021.htmlhttp://seclists.org/fulldisclosure/2021/Jul/54http://seclists.org/fulldisclosure/2021/Jul/55http://seclists.org/fulldisclosure/2021/Jul/58http://seclists.org/fulldisclosure/2021/Jul/59https://bugzilla.redhat.com/show_bug.cgi?id=1954242https://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3Ehttps://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3Ehttps://lists.debian.org/debian-lts-announce/2021/05/msg00008.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BZOMV5J4PMZAORVT64BKLV6YIZAFDGX6/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QVM4UJ3376I6ZVOYMHBNX4GY3NIV52WV/https://security.gentoo.org/glsa/202107-05https://security.netapp.com/advisory/ntap-20210625-0002/https://support.apple.com/kb/HT212601https://support.apple.com/kb/HT212602https://support.apple.com/kb/HT212604https://support.apple.com/kb/HT212605https://www.oracle.com/security-alerts/cpuapr2022.htmlhttps://www.oracle.com/security-alerts/cpujul2022.htmlhttps://www.oracle.com/security-alerts/cpuoct2021.htmlhttps://cert-portal.siemens.com/productcert/html/ssa-398330.html
2021-05-18
Published