<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE glsa SYSTEM "http://www.gentoo.org/dtd/glsa.dtd"> <glsa id="200312-05"> <title>GnuPG: ElGamal signing keys compromised and format string vulnerability</title> <synopsis> A bug in GnuPG allows ElGamal signing keys to be compromised, and a format string bug in the gpgkeys_hkp utility may allow arbitrary code execution. </synopsis> <product type="ebuild">GnuPG</product> <announced>2003-12-12</announced> <revised count="01">2003-12-12</revised> <bug>34504</bug> <access>unknown</access> <affected> <package name="app-crypt/gnupg" auto="yes" arch="*"> <unaffected range="ge">1.2.3-r5</unaffected> <vulnerable range="le">1.2.3-r4</vulnerable> </package> </affected> <background> <p> GnuPG is a popular open source signing and encryption tool. </p> </background> <description> <p> Two flaws have been found in GnuPG 1.2.3. </p> <p> First, ElGamal signing keys can be compromised. These keys are not commonly used, but this is "a significant security failure which can lead to a compromise of almost all ElGamal keys used for signing. Note that this is a real world vulnerability which will reveal your private key within a few seconds". </p> <p> Second, there is a format string flaw in the 'gpgkeys_hkp' utility which "would allow a malicious keyserver in the worst case to execute an arbitrary code on the user's machine." </p> </description> <impact type="minimal"> <p> If you have used ElGamal keys for signing your private key can be compromised, and a malicious keyserver could remotely execute arbitrary code with the permissions of the user running gpgkeys_hkp. </p> </impact> <workaround> <p> There is no known workaround at this time. </p> </workaround> <resolution> <p> All users who have created ElGamal signing keys should immediately revoke them. In addition, all Gentoo Linux machines with gnupg installed should be updated to use gnupg-1.2.3-r5 or higher: </p> <code> # emerge sync # emerge -pv '>=app-crypt/gnupg-1.2.3-r5' # emerge '>=app-crypt/gnupg-1.2.3-r5' # emerge clean</code> </resolution> <references> <uri link="https://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0971">CAN-2003-0971</uri> <uri link="http://marc.theaimsgroup.com/?l=gnupg-announce&m=106992378510843&q=raw">GnuPG Announcement</uri> <uri link="http://www.s-quadra.com/advisories/Adv-20031203.txt">S-Quadra Advisory</uri> </references> </glsa>