ID

VAR-202105-1325

CVE

CVE-2021-25217

TITLE

ISC DHCP  buffer overflow vulnerability in

DESCRIPTION

In ISC DHCP 4.1-ESV-R1 -> 4.1-ESV-R16, ISC DHCP 4.4.0 -> 4.4.2 (Other branches of ISC DHCP (i.e., releases in the 4.0.x series or lower and releases in the 4.3.x series) are beyond their End-of-Life (EOL) and no longer supported by ISC. From inspection it is clear that the defect is also present in releases from those series, but they have not been officially tested for the vulnerability), The outcome of encountering the defect while reading a lease that will trigger it varies, according to: the component being affected (i.e., dhclient or dhcpd) whether the package was built as a 32-bit or 64-bit binary whether the compiler flag -fstack-protection-strong was used when compiling In dhclient, ISC has not successfully reproduced the error on a 64-bit system. However, on a 32-bit system it is possible to cause dhclient to crash when reading an improper lease, which could cause network connectivity problems for an affected system due to the absence of a running DHCP client process. In dhcpd, when run in DHCPv4 or DHCPv6 mode: if the dhcpd server binary was built for a 32-bit architecture AND the -fstack-protection-strong flag was specified to the compiler, dhcpd may exit while parsing a lease file containing an objectionable lease, resulting in lack of service to clients. Additionally, the offending lease and the lease immediately following it in the lease database may be improperly deleted. if the dhcpd server binary was built for a 64-bit architecture OR if the -fstack-protection-strong compiler flag was NOT specified, the crash will not occur, but it is possible for the offending lease and the lease which immediately followed it to be improperly deleted. ISC (Internet Systems Consortium) Provided by ISC DHCP contains a buffer overflow vulnerability. ISC DHCP contains a buffer overflow vulnerability due to a discrepancy between the processing of optional information encapsulated within network packets and information stored on disk. There is a discrepancy between the code that handles encapsulated option information in leases transmitted "on the wire" and the code which reads and parses lease information after it has been written to disk storage. The highest threat from this vulnerability is to data confidentiality and integrity as well as service availability. (CVE-2021-25217). Description: Red Hat Advanced Cluster Management for Kubernetes 2.3.0 images Red Hat Advanced Cluster Management for Kubernetes provides the capabilities to address common challenges that administrators and site reliability engineers face as they work across a range of public and private cloud environments. Clusters and applications are all visible and managed from a single console—with security policy built in. See the following Release Notes documentation, which will be updated shortly for this release, for additional details about this release: https://access.redhat.com/documentation/en-us/red_hat_advanced_cluster_mana gement_for_kubernetes/2.3/html/release_notes/ Security: * fastify-reply-from: crafted URL allows prefix scape of the proxied backend service (CVE-2021-21321) * fastify-http-proxy: crafted URL allows prefix scape of the proxied backend service (CVE-2021-21322) * nodejs-netmask: improper input validation of octal input data (CVE-2021-28918) * redis: Integer overflow via STRALGO LCS command (CVE-2021-29477) * redis: Integer overflow via COPY command for large intsets (CVE-2021-29478) * nodejs-glob-parent: Regular expression denial of service (CVE-2020-28469) * nodejs-lodash: ReDoS via the toNumber, trim and trimEnd functions (CVE-2020-28500) * golang.org/x/text: Panic in language.ParseAcceptLanguage while parsing - -u- extension (CVE-2020-28851) * golang.org/x/text: Panic in language.ParseAcceptLanguage while processing bcp47 tag (CVE-2020-28852) * nodejs-ansi_up: XSS due to insufficient URL sanitization (CVE-2021-3377) * oras: zip-slip vulnerability via oras-pull (CVE-2021-21272) * redis: integer overflow when configurable limit for maximum supported bulk input size is too big on 32-bit platforms (CVE-2021-21309) * nodejs-lodash: command injection via template (CVE-2021-23337) * nodejs-hosted-git-info: Regular Expression denial of service via shortcutMatch in fromUrl() (CVE-2021-23362) * browserslist: parsing of invalid queries could result in Regular Expression Denial of Service (ReDoS) (CVE-2021-23364) * nodejs-postcss: Regular expression denial of service during source map parsing (CVE-2021-23368) * nodejs-handlebars: Remote code execution when compiling untrusted compile templates with strict:true option (CVE-2021-23369) * nodejs-postcss: ReDoS via getAnnotationURL() and loadAnnotation() in lib/previous-map.js (CVE-2021-23382) * nodejs-handlebars: Remote code execution when compiling untrusted compile templates with compat:true option (CVE-2021-23383) * openssl: integer overflow in CipherUpdate (CVE-2021-23840) * openssl: NULL pointer dereference in X509_issuer_and_serial_hash() (CVE-2021-23841) * nodejs-ua-parser-js: ReDoS via malicious User-Agent header (CVE-2021-27292) * grafana: snapshot feature allow an unauthenticated remote attacker to trigger a DoS via a remote API call (CVE-2021-27358) * nodejs-is-svg: ReDoS via malicious string (CVE-2021-28092) * nodejs-netmask: incorrectly parses an IP address that has octal integer with invalid character (CVE-2021-29418) * ulikunitz/xz: Infinite loop in readUvarint allows for denial of service (CVE-2021-29482) * normalize-url: ReDoS for data URLs (CVE-2021-33502) * nodejs-trim-newlines: ReDoS in .end() method (CVE-2021-33623) * nodejs-path-parse: ReDoS via splitDeviceRe, splitTailRe and splitPathRe (CVE-2021-23343) * html-parse-stringify: Regular Expression DoS (CVE-2021-23346) * openssl: incorrect SSLv2 rollback protection (CVE-2021-23839) For more details about the security issues, including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE pages listed in the References section. Bugs: * RFE Make the source code for the endpoint-metrics-operator public (BZ# 1913444) * cluster became offline after apiserver health check (BZ# 1942589) 3. Bugs fixed (https://bugzilla.redhat.com/): 1913333 - CVE-2020-28851 golang.org/x/text: Panic in language.ParseAcceptLanguage while parsing -u- extension 1913338 - CVE-2020-28852 golang.org/x/text: Panic in language.ParseAcceptLanguage while processing bcp47 tag 1913444 - RFE Make the source code for the endpoint-metrics-operator public 1921286 - CVE-2021-21272 oras: zip-slip vulnerability via oras-pull 1927520 - RHACM 2.3.0 images 1928937 - CVE-2021-23337 nodejs-lodash: command injection via template 1928954 - CVE-2020-28500 nodejs-lodash: ReDoS via the toNumber, trim and trimEnd functions 1930294 - CVE-2021-23839 openssl: incorrect SSLv2 rollback protection 1930310 - CVE-2021-23841 openssl: NULL pointer dereference in X509_issuer_and_serial_hash() 1930324 - CVE-2021-23840 openssl: integer overflow in CipherUpdate 1932634 - CVE-2021-21309 redis: integer overflow when configurable limit for maximum supported bulk input size is too big on 32-bit platforms 1936427 - CVE-2021-3377 nodejs-ansi_up: XSS due to insufficient URL sanitization 1939103 - CVE-2021-28092 nodejs-is-svg: ReDoS via malicious string 1940196 - View Resource YAML option shows 404 error when reviewing a Subscription for an application 1940613 - CVE-2021-27292 nodejs-ua-parser-js: ReDoS via malicious User-Agent header 1941024 - CVE-2021-27358 grafana: snapshot feature allow an unauthenticated remote attacker to trigger a DoS via a remote API call 1941675 - CVE-2021-23346 html-parse-stringify: Regular Expression DoS 1942178 - CVE-2021-21321 fastify-reply-from: crafted URL allows prefix scape of the proxied backend service 1942182 - CVE-2021-21322 fastify-http-proxy: crafted URL allows prefix scape of the proxied backend service 1942589 - cluster became offline after apiserver health check 1943208 - CVE-2021-23362 nodejs-hosted-git-info: Regular Expression denial of service via shortcutMatch in fromUrl() 1944822 - CVE-2021-29418 nodejs-netmask: incorrectly parses an IP address that has octal integer with invalid character 1944827 - CVE-2021-28918 nodejs-netmask: improper input validation of octal input data 1945459 - CVE-2020-28469 nodejs-glob-parent: Regular expression denial of service 1948761 - CVE-2021-23369 nodejs-handlebars: Remote code execution when compiling untrusted compile templates with strict:true option 1948763 - CVE-2021-23368 nodejs-postcss: Regular expression denial of service during source map parsing 1954150 - CVE-2021-23382 nodejs-postcss: ReDoS via getAnnotationURL() and loadAnnotation() in lib/previous-map.js 1954368 - CVE-2021-29482 ulikunitz/xz: Infinite loop in readUvarint allows for denial of service 1955619 - CVE-2021-23364 browserslist: parsing of invalid queries could result in Regular Expression Denial of Service (ReDoS) 1956688 - CVE-2021-23383 nodejs-handlebars: Remote code execution when compiling untrusted compile templates with compat:true option 1956818 - CVE-2021-23343 nodejs-path-parse: ReDoS via splitDeviceRe, splitTailRe and splitPathRe 1957410 - CVE-2021-29477 redis: Integer overflow via STRALGO LCS command 1957414 - CVE-2021-29478 redis: Integer overflow via COPY command for large intsets 1964461 - CVE-2021-33502 normalize-url: ReDoS for data URLs 1966615 - CVE-2021-33623 nodejs-trim-newlines: ReDoS in .end() method 1968122 - clusterdeployment fails because hiveadmission sc does not have correct permissions 1972703 - Subctl fails to join cluster, since it cannot auto-generate a valid cluster id 1983131 - Defragmenting an etcd member doesn't reduce the DB size (7.5GB) on a setup with ~1000 spoke clusters 5. 6 ELS) - i386, s390x, x86_64 3. These packages include redhat-release-virtualization-host. RHVH features a Cockpit user interface for monitoring the host's resources and performing administrative tasks. Solution: Before applying this update, make sure all previously released errata relevant to your system have been applied. -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 ==================================================================== Red Hat Security Advisory Synopsis: Important: dhcp security update Advisory ID: RHSA-2021:2357-01 Product: Red Hat Enterprise Linux Advisory URL: https://access.redhat.com/errata/RHSA-2021:2357 Issue date: 2021-06-09 CVE Names: CVE-2021-25217 ==================================================================== 1. Summary: An update for dhcp is now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. 2. Relevant releases/architectures: Red Hat Enterprise Linux Client (v. 7) - x86_64 Red Hat Enterprise Linux Client Optional (v. 7) - x86_64 Red Hat Enterprise Linux ComputeNode (v. 7) - x86_64 Red Hat Enterprise Linux ComputeNode Optional (v. 7) - x86_64 Red Hat Enterprise Linux Server (v. 7) - ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Server Optional (v. 7) - ppc64, ppc64le, s390x, x86_64 Red Hat Enterprise Linux Workstation (v. 7) - x86_64 Red Hat Enterprise Linux Workstation Optional (v. 7) - x86_64 3. Description: The Dynamic Host Configuration Protocol (DHCP) is a protocol that allows individual devices on an IP network to get their own network configuration information, including an IP address, a subnet mask, and a broadcast address. The dhcp packages provide a relay agent and ISC DHCP service required to enable and administer DHCP on a network. Security Fix(es): * dhcp: stack-based buffer overflow when parsing statements with colon-separated hex digits in config or lease files in dhcpd and dhclient (CVE-2021-25217) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. 4. Solution: For details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 5. Bugs fixed (https://bugzilla.redhat.com/): 1963258 - CVE-2021-25217 dhcp: stack-based buffer overflow when parsing statements with colon-separated hex digits in config or lease files in dhcpd and dhclient 6. Package List: Red Hat Enterprise Linux Client (v. 7): Source: dhcp-4.2.5-83.el7_9.1.src.rpm x86_64: dhclient-4.2.5-83.el7_9.1.x86_64.rpm dhcp-common-4.2.5-83.el7_9.1.x86_64.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.i686.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.x86_64.rpm dhcp-libs-4.2.5-83.el7_9.1.i686.rpm dhcp-libs-4.2.5-83.el7_9.1.x86_64.rpm Red Hat Enterprise Linux Client Optional (v. 7): x86_64: dhcp-4.2.5-83.el7_9.1.x86_64.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.i686.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.x86_64.rpm dhcp-devel-4.2.5-83.el7_9.1.i686.rpm dhcp-devel-4.2.5-83.el7_9.1.x86_64.rpm Red Hat Enterprise Linux ComputeNode (v. 7): Source: dhcp-4.2.5-83.el7_9.1.src.rpm x86_64: dhclient-4.2.5-83.el7_9.1.x86_64.rpm dhcp-common-4.2.5-83.el7_9.1.x86_64.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.i686.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.x86_64.rpm dhcp-libs-4.2.5-83.el7_9.1.i686.rpm dhcp-libs-4.2.5-83.el7_9.1.x86_64.rpm Red Hat Enterprise Linux ComputeNode Optional (v. 7): x86_64: dhcp-4.2.5-83.el7_9.1.x86_64.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.i686.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.x86_64.rpm dhcp-devel-4.2.5-83.el7_9.1.i686.rpm dhcp-devel-4.2.5-83.el7_9.1.x86_64.rpm Red Hat Enterprise Linux Server (v. 7): Source: dhcp-4.2.5-83.el7_9.1.src.rpm ppc64: dhclient-4.2.5-83.el7_9.1.ppc64.rpm dhcp-4.2.5-83.el7_9.1.ppc64.rpm dhcp-common-4.2.5-83.el7_9.1.ppc64.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.ppc.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.ppc64.rpm dhcp-libs-4.2.5-83.el7_9.1.ppc.rpm dhcp-libs-4.2.5-83.el7_9.1.ppc64.rpm ppc64le: dhclient-4.2.5-83.el7_9.1.ppc64le.rpm dhcp-4.2.5-83.el7_9.1.ppc64le.rpm dhcp-common-4.2.5-83.el7_9.1.ppc64le.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.ppc64le.rpm dhcp-libs-4.2.5-83.el7_9.1.ppc64le.rpm s390x: dhclient-4.2.5-83.el7_9.1.s390x.rpm dhcp-4.2.5-83.el7_9.1.s390x.rpm dhcp-common-4.2.5-83.el7_9.1.s390x.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.s390.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.s390x.rpm dhcp-libs-4.2.5-83.el7_9.1.s390.rpm dhcp-libs-4.2.5-83.el7_9.1.s390x.rpm x86_64: dhclient-4.2.5-83.el7_9.1.x86_64.rpm dhcp-4.2.5-83.el7_9.1.x86_64.rpm dhcp-common-4.2.5-83.el7_9.1.x86_64.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.i686.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.x86_64.rpm dhcp-libs-4.2.5-83.el7_9.1.i686.rpm dhcp-libs-4.2.5-83.el7_9.1.x86_64.rpm Red Hat Enterprise Linux Server Optional (v. 7): ppc64: dhcp-debuginfo-4.2.5-83.el7_9.1.ppc.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.ppc64.rpm dhcp-devel-4.2.5-83.el7_9.1.ppc.rpm dhcp-devel-4.2.5-83.el7_9.1.ppc64.rpm ppc64le: dhcp-debuginfo-4.2.5-83.el7_9.1.ppc64le.rpm dhcp-devel-4.2.5-83.el7_9.1.ppc64le.rpm s390x: dhcp-debuginfo-4.2.5-83.el7_9.1.s390.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.s390x.rpm dhcp-devel-4.2.5-83.el7_9.1.s390.rpm dhcp-devel-4.2.5-83.el7_9.1.s390x.rpm x86_64: dhcp-debuginfo-4.2.5-83.el7_9.1.i686.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.x86_64.rpm dhcp-devel-4.2.5-83.el7_9.1.i686.rpm dhcp-devel-4.2.5-83.el7_9.1.x86_64.rpm Red Hat Enterprise Linux Workstation (v. 7): Source: dhcp-4.2.5-83.el7_9.1.src.rpm x86_64: dhclient-4.2.5-83.el7_9.1.x86_64.rpm dhcp-4.2.5-83.el7_9.1.x86_64.rpm dhcp-common-4.2.5-83.el7_9.1.x86_64.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.i686.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.x86_64.rpm dhcp-libs-4.2.5-83.el7_9.1.i686.rpm dhcp-libs-4.2.5-83.el7_9.1.x86_64.rpm Red Hat Enterprise Linux Workstation Optional (v. 7): x86_64: dhcp-debuginfo-4.2.5-83.el7_9.1.i686.rpm dhcp-debuginfo-4.2.5-83.el7_9.1.x86_64.rpm dhcp-devel-4.2.5-83.el7_9.1.i686.rpm dhcp-devel-4.2.5-83.el7_9.1.x86_64.rpm These packages are GPG signed by Red Hat for security. Our key and details on how to verify the signature are available from https://access.redhat.com/security/team/key/ 7. References: https://access.redhat.com/security/cve/CVE-2021-25217 https://access.redhat.com/security/updates/classification/#important 8. Contact: The Red Hat security contact is <secalert@redhat.com>. More contact details at https://access.redhat.com/security/team/contact/ Copyright 2021 Red Hat, Inc. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIVAwUBYMCeytzjgjWX9erEAQgPYw/+K6NTT5tvNy0WHRy46UioFuzIbxlMOPzm zXmk61B2Dgod7DCU3EbF9u7nSViaQds11pDCrTejH70WrqNQSaWMhsASgtNmQ42q 0oVWQwqyB8mP/73BwYJQ84eZDGwsyqQf/9MO96g4c0jlZOAu9vSxvSflQ4DY8m9L 0+pk3/zHOsUz3Za7Ns/1wa8pmq3hxAt0z6Z6ri0Ka8CEHg7W7ELGC67ih1BOcpP5 mdWOSfTW+F1EzmerDW0eom09R/Ndfo/FdGeCbEq1K6kvcrPy4e/tsyBCquPYPFar aTADxJPMObDTY0dJhqw1qZ5cERLnhJaj8GzWc0Ne2KIAFig/NcVhEZL8RtvrNWhO JIaVZ7zK6bi1VASVVIAP8yQzwdZFEbfMREOa705gMvXMz1Ux08YvsbrelD/LeJXe 45C2+zGvM7KDd/AlrhopZPbBJI07tbNe8qWzFggJtBTMVg28i5K7DjFjvASFZFrV 8nKdWae1GOEtH23fygGOoW4m0KkGWd1Tc/lte6Wy788KOa/yF3IQkWeTSo5KG33Q UHCzx6NzHyeAgW7K9QvvpIjfbxIAyBbebsIkhOhySjfsAp28lKkaZZRVF/sNWIvG GRibEMi366KUTR5AiTMAjHoYgIDzp7nywWiYBhf9SuNgqV3kG0Yz7fd1ac0+qcH5 zPKanVJNoQs=9+pl -----END PGP SIGNATURE----- -- RHSA-announce mailing list RHSA-announce@redhat.com https://listman.redhat.com/mailman/listinfo/rhsa-announce . 8) - aarch64, noarch, ppc64le, s390x, x86_64 3

AFFECTED PRODUCTS

CVSS

PROBLEMTYPE DATA

TYPE

overflow

PATCH

EXTERNAL IDS

REFERENCES

CREDITS

Red Hat

SOURCES

LAST UPDATE DATE

2026-02-07T22:57:58.559000+00:00

SOURCES UPDATE DATE

SOURCES RELEASE DATE