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Gentoo Linux Security Advisory GLSA 202105-20 |
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https://security.gentoo.org/ |
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Severity: Low |
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Title: Dnsmasq: DNS cache poisoning |
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Date: May 26, 2021 |
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Bugs: #782130 |
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ID: 202105-20 |
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Synopsis |
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======== |
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|
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Use of insufficient randomness in Dnsmasq might lead to DNS Cache |
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Poisoning. |
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Background |
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========== |
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|
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Dnsmasq is a lightweight and easily-configurable DNS forwarder and DHCP |
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server. |
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|
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Affected packages |
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================= |
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|
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------------------------------------------------------------------- |
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Package / Vulnerable / Unaffected |
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------------------------------------------------------------------- |
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1 net-dns/dnsmasq < 2.85 >= 2.85 |
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Description |
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=========== |
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|
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It was discovered that Dnsmasq, when configured with |
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--server=<address>@<interface> or similar (e.g. through dbus), |
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configured a fixed UDP port for all outgoing queries to the specified |
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upstream DNS server. |
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|
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Impact |
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====== |
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|
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An attacker, by sending malicious crafted DNS responses, could perform |
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a DNS Cache Poisoning attack. |
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|
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Workaround |
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========== |
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There is no known workaround at this time. |
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Resolution |
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========== |
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All Dnsmasq users should upgrade to the latest version: |
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# emerge --sync |
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# emerge --ask --oneshot --verbose ">=net-dns/dnsmasq-2.85" |
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|
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References |
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========== |
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|
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[ 1 ] CVE-2021-3448 |
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https://nvd.nist.gov/vuln/detail/CVE-2021-3448 |
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Availability |
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============ |
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This GLSA and any updates to it are available for viewing at |
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the Gentoo Security Website: |
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https://security.gentoo.org/glsa/202105-20 |
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|
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Concerns? |
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========= |
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Security is a primary focus of Gentoo Linux and ensuring the |
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confidentiality and security of our users' machines is of utmost |
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importance to us. Any security concerns should be addressed to |
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security@g.o or alternatively, you may file a bug at |
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https://bugs.gentoo.org. |
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|
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License |
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======= |
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Copyright 2021 Gentoo Foundation, Inc; referenced text |
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belongs to its owner(s). |
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|
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The contents of this document are licensed under the |
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Creative Commons - Attribution / Share Alike license. |
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|
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https://creativecommons.org/licenses/by-sa/2.5 |
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