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-----BEGIN PGP SIGNED MESSAGE----- |
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Hash: SHA1 |
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|
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- - --------------------------------------------------------------------- |
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GENTOO LINUX SECURITY ANNOUNCEMENT 200302-10 |
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|
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PACKAGE : openssl |
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SUMMARY : timing based attack |
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DATE : 2003-02-20 17:28 UTC |
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EXPLOIT : remote |
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|
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|
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- From advisory: |
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|
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"The attack assumes that multiple SSL or TLS connections involve a |
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common fixed plaintext block, such as a password. An active attacker |
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can substitute specifically made-up ciphertext blocks for blocks sent |
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by legitimate SSL/TLS parties and measure the time until a response |
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arrives: SSL/TLS includes data authentication to ensure that such |
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modified ciphertext blocks will be rejected by the peer (and the |
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connection aborted), but the attacker may be able to use timing |
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observations to distinguish between two different error cases, namely |
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block cipher padding errors and MAC verification errors. This is |
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sufficient for an adaptive attack that finally can obtain the complete |
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plaintext block." |
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|
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Read the full advisory at: |
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http://www.openssl.org/news/secadv_20030219.txt |
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|
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SOLUTION |
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|
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It is recommended that all Gentoo Linux users who are running |
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dev-libs/openssl upgrade to openssl-0.9.6i or openssl-0.9.7a |
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as follows: |
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|
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emerge sync |
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emerge -u openssl |
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emerge clean |
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|
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aliz@g.o - GnuPG key is available at http://cvs.gentoo.org/~aliz |
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- - --------------------------------------------------------------------- |
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-----BEGIN PGP SIGNATURE----- |
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Version: GnuPG v1.2.1 (GNU/Linux) |
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iD8DBQE+VRA6fT7nyhUpoZMRAhR+AKCLuEcwWB26YqBz6p05h0dt55QTNACdECVZ |
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42cR0GYdllhIxECgdUhrcVA= |
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=6DOA |
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-----END PGP SIGNATURE----- |
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