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Gentoo Linux Security Advisory GLSA 200603-08 |
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http://security.gentoo.org/ |
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Severity: Normal |
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Title: GnuPG: Incorrect signature verification |
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Date: March 10, 2006 |
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Bugs: #125217 |
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ID: 200603-08 |
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Synopsis |
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======== |
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|
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GnuPG may erroneously report a modified or unsigned message has a valid |
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digital signature. |
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Background |
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========== |
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|
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The GNU Privacy Guard, GnuPG, is a free replacement for the PGP suite |
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of cryptographic software that may be used without restriction, as it |
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does not rely on any patented algorithms. GnuPG can be used to |
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digitally sign messages, a method of ensuring the authenticity of a |
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message using public key cryptography. |
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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 app-crypt/gnupg < 1.4.2.2 >= 1.4.2.2 |
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|
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Description |
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=========== |
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|
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OpenPGP is the standard that defines the format of digital signatures |
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supported by GnuPG. OpenPGP signatures consist of multiple sections, in |
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a strictly defined order. Tavis Ormandy of the Gentoo Linux Security |
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Audit Team discovered that certain illegal signature formats could |
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allow signed data to be modified without detection. GnuPG has |
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previously attempted to be lenient when processing malformed or legacy |
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signature formats, but this has now been found to be insecure. |
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|
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Impact |
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====== |
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|
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A remote attacker may be able to construct or modify a digitally-signed |
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message, potentially allowing them to bypass authentication systems, or |
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impersonate another user. |
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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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|
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Resolution |
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========== |
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All GnuPG users should upgrade to the latest version: |
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# emerge --sync |
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# emerge --ask --oneshot --verbose ">=app-crypt/gnupg-1.4.2.2" |
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|
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References |
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========== |
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|
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[ 1 ] CVE-2006-0049 |
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http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2006-0049 |
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[ 2 ] GnuPG Announcement |
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http://lists.gnupg.org/pipermail/gnupg-announce/2006q1/000216.html |
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|
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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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http://security.gentoo.org/glsa/glsa-200603-08.xml |
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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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http://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 2006 Gentoo Foundation, Inc; referenced text |
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belongs to its owner(s). |
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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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http://creativecommons.org/licenses/by-sa/2.0 |
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