CVE-2021-3517
published 2021-05-19CVE-2021-3517: 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…
PriorityP260high8.6CVSS 3.1
AVNACLPRNUINSUCLILAH
EPSS
16.99%
97.1th percentile
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.
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 | — | — |
| 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 | — | — |
| netapp | e-series_santricity_os_controller | 11.0.0 – 11.70.1 | — |
| 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 | mysql_workbench | <= 8.0.26 | — |
| oracle | openjdk | — | — |
| oracle | peoplesoft_enterprise_peopletools | — | — |
| oracle | real_user_experience_insight | — | — |
| oracle | real_user_experience_insight | — | — |
| oracle | zfs_storage_appliance_kit | — | — |
| redhat | enterprise_linux | — | — |
| satellite_el8 | rubygem-nokogiri | — | — |
| xmlsoft | libxml2 | < 2.9.11 | 2.9.11 |
CVSS provenance
nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
ghsa7.5HIGH
osv9.1CRITICAL
vendor_ubuntu9.1CRITICAL
vendor_debian8.6HIGH
vendor_msrc8.6HIGH
vendor_oracle8.6HIGH
vendor_redhat8.6HIGH
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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 contains libxml Out-of-bounds Write vulnerability
ghsa·2022-05-24
CVE-2021-3517 [HIGH] CWE-787 Nokogiri contains libxml Out-of-bounds Write vulnerability
Nokogiri contains libxml Out-of-bounds Write vulnerability
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.
Nokogiri prior to version 1.11.4 used a vulnerable version of libxml2. Nokogiri 1.11.4 updated libxml2 to version 2.9.11 to address this and other vulnerabilities in libxml2.
OSV
Nokogiri contains libxml Out-of-bounds Write vulnerability
osv·2022-05-24
CVE-2021-3517 [HIGH] Nokogiri contains libxml Out-of-bounds Write vulnerability
Nokogiri contains libxml Out-of-bounds Write vulnerability
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.
Nokogiri prior to version 1.11.4 used a vulnerable version of libxml2. Nokogiri 1.11.4 updated libxml2 to version 2.9.11 to address this and other vulnerabilities in libxml2.
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-2021-3517: There is a flaw in the xml entity encoding functionality of libxml2 in versions before 2
osv·2021-05-19·CVSS 8.6
CVE-2021-3517 [HIGH] CVE-2021-3517: There is a flaw in the xml entity encoding functionality of libxml2 in versions before 2
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.
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
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 Systems Risk Matrix: Operating System Image — CVE-2021-3517
vendor_oracle·2022-01-15·CVSS 8.6
CVE-2021-3517 [HIGH] Oracle Oracle Systems Risk Matrix: Operating System Image — CVE-2021-3517
Oracle Oracle Systems Risk Matrix: Operating System Image vulnerability
CVE: CVE-2021-3517
CVSS: 8.6
Protocol: Multiple
Remote exploit: Yes
Affected versions: Network
Advisory: cpujan2022 (JAN 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
CISA ICS
Hitachi Energy RTU500 series
cisa_ics·2021-12-02·CVSS 3.7
[LOW] Hitachi Energy RTU500 series
## 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 RTU500 series
Last RevisedDecember 02, 2021
Alert CodeICSA-21-336-08
## 1. EXECUTIVE SUMMARY
- CVSS v3 8.6
- ATTENTION: Exploitable remotely/low attack complexity
- Vendor: Hitachi Energy
- Equipment: RTU500 series
- Vulnerabilities: Observable Discrepancy, Buffer Over-read, Out-of-bounds Read
## 2. RISK EVALUATION
Successful exploitation of these vulnerabilities could allow an attacker to eavesdrop on traffic, retrieve information from memory, or cause a denial-of-service condition.
## 3. TECHNICAL DETAILS
## 3.1 AFFECTED PRODUCTS
The following versions
Oracle
Oracle Oracle Java SE Risk Matrix: JavaFX (libxml) — CVE-2021-3517
vendor_oracle·2021-10-15·CVSS 8.6
CVE-2021-3517 [HIGH] Oracle Oracle Java SE Risk Matrix: JavaFX (libxml) — CVE-2021-3517
Oracle Oracle Java SE Risk Matrix: JavaFX (libxml) vulnerability
CVE: CVE-2021-3517
CVSS: 8.6
Protocol: Multiple
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 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 affect
vendor_msrc·2021-05-11·CVSS 8.6
CVE-2021-3517 [HIGH] CWE-787 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 affect
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.
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
Red Hat
libxml2: Heap-based buffer overflow in xmlEncodeEntitiesInternal() in entities.c
vendor_redhat·2021-04-22·CVSS 8.6
CVE-2021-3517 [HIGH] CWE-787 libxml2: Heap-based buffer overflow in xmlEncodeEntitiesInternal() in entities.c
libxml2: Heap-based buffer overflow in xmlEncodeEntitiesInternal() in entities.c
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.
There is a flaw in the xml entity encoding functionality of libxml2. 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.
Debian
CVE-2021-3517: libxml2 - There is a flaw in the xml entity encoding functionality of libxml2 in versions ...
vendor_debian·2021·CVSS 8.6
CVE-2021-3517 [HIGH] CVE-2021-3517: libxml2 - There is a flaw in the xml entity encoding functionality of libxml2 in versions ...
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.
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)
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-2021-3517 libxml2: Heap-based buffer overflow in xmlEncodeEntitiesInternal() in entities.c
bugzilla·2021-04-27·CVSS 8.6
CVE-2021-3517 [HIGH] CVE-2021-3517 libxml2: Heap-based buffer overflow in xmlEncodeEntitiesInternal() in entities.c
CVE-2021-3517 libxml2: Heap-based buffer overflow in xmlEncodeEntitiesInternal() in entities.c
A heap-based buffer overflow was found in libxml2 when processing truncated UTF-8 input.
Reference:
https://gitlab.gnome.org/GNOME/libxml2/-/issues/235
Upstream patch:
https://gitlab.gnome.org/GNOME/libxml2/-/commit/bf22713507fe1fc3a2c4b525cf0a88c2dc87a3a2
Discussion:
Created libxml2 tracking bugs for this issue:
Affects: fedora-all [bug 1954234]
Created mingw-libxml2 tracking bugs for this issue:
Affects: fedora-all [bug 1954233]
---
Acknowledgments:
Name: zodf0055980 (SQLab NCTU Taiwan)
---
Upstream patch: https://gitlab.gnome.org/GNOME/libxml2/-/commit/bf22713507fe1fc3a2c4b525cf0a88c2dc87a3a2
---
Statement:
This flaw is out of support scope for Red Hat Enterprise Linux 6 and 7
https://bugzilla.redhat.com/show_bug.cgi?id=1954232https://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://security.netapp.com/advisory/ntap-20211022-0004/https://www.oracle.com/security-alerts/cpuapr2022.htmlhttps://www.oracle.com/security-alerts/cpujan2022.htmlhttps://www.oracle.com/security-alerts/cpujul2022.htmlhttps://www.oracle.com/security-alerts/cpuoct2021.htmlhttps://bugzilla.redhat.com/show_bug.cgi?id=1954232https://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://security.netapp.com/advisory/ntap-20211022-0004/https://www.oracle.com/security-alerts/cpuapr2022.htmlhttps://www.oracle.com/security-alerts/cpujan2022.htmlhttps://www.oracle.com/security-alerts/cpujul2022.htmlhttps://www.oracle.com/security-alerts/cpuoct2021.htmlhttps://cert-portal.siemens.com/productcert/html/ssa-398330.html
2021-05-19
Published