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Gentoo Linux Security Advisory GLSA 202210-33 |
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https://security.gentoo.org/ |
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|
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Severity: Normal |
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Title: Libtirpc: Denial of Service |
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Date: October 31, 2022 |
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Bugs: #859634 |
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ID: 202210-33 |
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|
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Synopsis |
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======== |
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|
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A vulnerability has been discovered in Libtirpc which could result in |
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denial of service. |
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|
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Background |
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========== |
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|
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Libtirpc is a port of Sun's Transport-Independent RPC library to Linux. |
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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-libs/libtirpc < 1.3.2 >= 1.3.2 |
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|
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Description |
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=========== |
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|
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Currently svc_run does not handle poll timeout and rendezvous_request |
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does not handle EMFILE error returned from accept(2 as it used to. |
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These two missing functionality were removed by commit b2c9430f46c4. |
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|
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The effect of not handling poll timeout allows idle TCP conections |
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to remain ESTABLISHED indefinitely. When the number of connections |
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reaches the limit of the open file descriptors (ulimit -n) then |
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accept(2) fails with EMFILE. Since there is no handling of EMFILE |
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error this causes svc_run() to get in a tight loop calling accept(2). |
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This resulting in the RPC service of svc_run is being down, it's |
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no longer able to service any requests. |
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|
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Due to a lack of handling of certain error cases, connections to |
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Libtirpc could remain ESTABLISHED indefinitely. |
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|
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Impact |
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====== |
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|
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Denial of service can be achieved via establishing enough connections to |
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Libtirpc to reach the limit of open file descriptors for the process. |
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|
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Workaround |
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========== |
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|
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There is no known workaround at this time. |
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|
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Resolution |
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========== |
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|
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All Libtirpc users should upgrade to the latest version: |
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|
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# emerge --sync |
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# emerge --ask --oneshot --verbose ">=net-libs/libtirpc-1.3.2" |
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|
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References |
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========== |
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|
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[ 1 ] CVE-2021-46828 |
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https://nvd.nist.gov/vuln/detail/CVE-2021-46828 |
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|
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Availability |
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============ |
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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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|
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https://security.gentoo.org/glsa/202210-33 |
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|
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Concerns? |
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========= |
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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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|
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Copyright 2022 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 |