星球
USN-1108-2: DHCP vulnerability
Ubuntu Security Notice USN-1108-2
19th April, 2011
dhcp3 vulnerability
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 10.10
- Ubuntu 10.04 LTS
- Ubuntu 9.10
Summary
An attacker's DHCP server could send crafted responses to your computer and
cause it to run programs as root.
Software description
- dhcp3
- DHCP Client
Details
USN-1108-1 fixed vulnerabilities in DHCP. Due to an error, the patch to fix
the vulnerability was not properly applied on Ubuntu 9.10 and higher. This
update fixes the problem.
Original advisory details:
Sebastian Krahmer discovered that the dhclient utility incorrectly filtered
crafted responses. An attacker could use this flaw with a malicious DHCP
server to execute arbitrary code, resulting in root privilege escalation.
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 10.10:
dhcp3-client
3.1.3-2ubuntu6.2
- Ubuntu 10.04 LTS:
dhcp3-client
3.1.3-2ubuntu3.2
- Ubuntu 9.10:
dhcp3-client
3.1.2-1ubuntu7.3
In general, a standard system update will make all the necessary changes.
References
USN-1114-1: KDENetwork vulnerability
Ubuntu Security Notice USN-1114-1
18th April, 2011
kdenetwork vulnerability
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 10.10
- Ubuntu 10.04 LTS
- Ubuntu 9.10
Summary
An attacker could overwrite files owned by the user if KGet opened a
crafted metalink file.
Software description
- kdenetwork
- networking applications for KDE 4
Details
It was discovered that KGet did not properly perform input validation when
processing metalink files. If a user were tricked into opening a crafted
metalink file, a remote attacker could overwrite files via directory
traversal, which could eventually lead to arbitrary code execution.
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 10.10:
kget
4:4.5.1-0ubuntu2.2
- Ubuntu 10.04 LTS:
kget
4:4.4.5-0ubuntu1.1
- Ubuntu 9.10:
kget
4:4.3.2-0ubuntu4.5
After a standard system update you need to restart KGet to make all the
necessary changes.
References
USN-1113-1: Postfix vulnerabilities
Ubuntu Security Notice USN-1113-1
18th April, 2011
postfix vulnerabilities
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 10.10
- Ubuntu 10.04 LTS
- Ubuntu 9.10
- Ubuntu 8.04 LTS
- Ubuntu 6.06 LTS
Summary
An attacker could send crafted input to Postfix and cause it to reveal
confidential information.
Software description
- postfix
- High-performance mail transport agent
Details
It was discovered that the Postfix package incorrectly granted write access
on the PID directory to the postfix user. A local attacker could use this
flaw to possibly conduct a symlink attack and overwrite arbitrary files.
This issue only affected Ubuntu 6.06 LTS and 8.04 LTS. (CVE-2009-2939)
Wietse Venema discovered that Postfix incorrectly handled cleartext
commands after TLS is in place. A remote attacker could exploit this to
inject cleartext commands into TLS sessions, and possibly obtain
confidential information such as passwords. (CVE-2011-0411)
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 10.10:
postfix
2.7.1-1ubuntu0.1
- Ubuntu 10.04 LTS:
postfix
2.7.0-1ubuntu0.1
- Ubuntu 9.10:
postfix
2.6.5-3ubuntu0.1
- Ubuntu 8.04 LTS:
postfix
2.5.1-2ubuntu1.3
- Ubuntu 6.06 LTS:
postfix
2.2.10-1ubuntu0.3
In general, a standard system update will make all the necessary changes.
References
USN-1108-1: DHCP vulnerability
Ubuntu Security Notice USN-1108-1
11th April, 2011
dhcp3 vulnerability
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 10.10
- Ubuntu 10.04 LTS
- Ubuntu 9.10
- Ubuntu 8.04 LTS
- Ubuntu 6.06 LTS
Summary
An attacker's DHCP server could send crafted responses to your computer
and cause it to run programs as root.
Software description
- dhcp3
- DHCP Client
Details
Sebastian Krahmer discovered that the dhclient utility incorrectly filtered
crafted responses. An attacker could use this flaw with a malicious DHCP
server to execute arbitrary code, resulting in root privilege escalation.
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 10.10:
dhcp3-client
3.1.3-2ubuntu6.1
- Ubuntu 10.04 LTS:
dhcp3-client
3.1.3-2ubuntu3.1
- Ubuntu 9.10:
dhcp3-client
3.1.2-1ubuntu7.2
- Ubuntu 8.04 LTS:
dhcp3-client
3.0.6.dfsg-1ubuntu9.2
- Ubuntu 6.06 LTS:
dhcp3-client
3.0.3-6ubuntu7.2
In general, a standard system update will make all the necessary changes.
References
USN-1109-1: GIMP vulnerabilities
Ubuntu Security Notice USN-1109-1
13th April, 2011
gimp vulnerabilities
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 10.10
- Ubuntu 10.04 LTS
- Ubuntu 9.10
- Ubuntu 8.04 LTS
Summary
GIMP could be made to run programs as your login if it opened a
specially crafted file.
Software description
- gimp
- The GNU Image Manipulation Program
Details
It was discovered that GIMP incorrectly handled malformed data in certain
plugin configuration files. If a user were tricked into opening a specially
crafted plugin configuration file, an attacker could cause GIMP to crash,
or possibly execute arbitrary code with the user's privileges. The default
compiler options for affected releases should reduce the vulnerability to a
denial of service. (CVE-2010-4540, CVE-2010-4541, CVE-2010-4542)
It was discovered that GIMP incorrectly handled malformed PSP image files.
If a user were tricked into opening a specially crafted PSP image file, an
attacker could cause GIMP to crash, or possibly execute arbitrary code with
the user's privileges. (CVE-2010-4543)
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 10.10:
gimp
2.6.10-1ubuntu3.2
- Ubuntu 10.04 LTS:
gimp
2.6.8-2ubuntu1.2
- Ubuntu 9.10:
gimp
2.6.7-1ubuntu1.2
- Ubuntu 8.04 LTS:
gimp
2.4.5-1ubuntu2.3
After a standard system update you need to restart GIMP to make all the
necessary changes.
References
USN-1110-1: KDE-Libs vulnerabilities
Ubuntu Security Notice USN-1110-1
14th April, 2011
kde4libs vulnerabilities
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 10.10
- Ubuntu 10.04 LTS
- Ubuntu 9.10
Summary
An attacker could send crafted input to Konqueror to view sensitive
information.
Software description
- kde4libs
- KDE 4 core applications
Details
It was discovered that KDE KSSL did not properly verify X.509 certificates
when the certificate was issued for an IP address. An attacker could
exploit this to perform a man in the middle attack to view sensitive
information or alter encrypted communications. (CVE-2011-1094)
Tim Brown discovered that KDE KHTML did not properly escape URLs from
externally generated error pages. An attacker could expoit this to conduct
cross-site scripting attacks. With cross-site scripting vulnerabilities, if
a user were tricked into viewing server output during a crafted server
request, a remote attacker could exploit this to modify the contents, or
steal confidential data (such as passwords), within the same domain.
(CVE-2011-1168)
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 10.10:
libkio5
4:4.5.1-0ubuntu8.1
libkhtml5
4:4.5.1-0ubuntu8.1
- Ubuntu 10.04 LTS:
kdelibs5
4:4.4.5-0ubuntu1.1
- Ubuntu 9.10:
kdelibs5
4:4.3.2-0ubuntu7.3
After a standard system update you need to restart any applications that
use KSSL or KHTML, such as Konqueror, to make all the necessary changes.
References
SSH 的公私錀生成說明
請在命令列鍵入如下指令：
$ ssh-keygen -t rsa -b 4096
Generating public/private rsa key pair.
Enter file in which to save the key (/home/tmp/.ssh/id_rsa): <<按 Enter ，使用預設值>>
Enter passphrase (empty for no passphrase): <<設個私錀密碼，請大於 5 個字元>>
Enter same passphrase again: <<確認剛剛的私錀密碼>>
Your identification has been saved in /home/tmp/.ssh/id_rsa.
Your public key has been saved in /home/tmp/.ssh/id_rsa.pub.
The key fingerprint is:
72:fb:40:ba:8a:40:be:48:03:bd:20:13:6d:83:cb:d0 tmp@core2duo
The key's randomart image is:
+--[ RSA 4096]----+
| |
| + |
|+ A |
|o= . |
|*o. T . S |
|=o . = . |
|.-. . o |
|o.o. . o |
|... ... . |
+-----------------+
這樣，你的公錀就是 ~/.ssh/id_rsa.pub 而私錀就是 ~/.ssh/id_rsa 。
$ cat ~/.ssh/id_rsa.pub
ssh-rsa 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 tmp@core2duo
把上面的公錀內容放到你想登入的 Linux/Mac 機器中的 ~/.ssh/authorized_keys2 (這個檔，其實是看系統管理員是怎麼設定的，只不過一般的 Linux 套件都是用這個作預設值)中，這樣你就能使用這一對公私錀登入遠端機器了。
Windows:
就比較麻煩了，請去下載 puttygen.exe 程式，執行它後如下圖：
選擇 SSH-2 RSA 及輸入 4096 的 Number of bits in a generated key 後，再按下 Generate 按鈕，讓滑鼠停留在綠色生成桿的下方空白處，並胡亂移動滑鼠遊標，讓 puttygen.exe 得到亂數種子，待進度達百分百後，可得到下圖：
選取的藍色文字即公錀內容，請貼到你欲登入的 Linux/Mac 機器中的 ~/.ssh/authorized_keys2 中，而私錀部份，請在設定密碼「Key passphrase」及確認密碼「Confirm passphrase」後，按下 Save private key 按鈕以存檔至系統硬碟。
最後，請保護好你的私錀檔(最好不要離開生成它的機器硬碟)，遺失它或是被別人盜取後的代價相當大。 Good Luck!
我的Ardour2怎麼沒辦法隨便移動位置、迴帶？
How to get a free HTTPS web certification authority by StartSSL.com
- 註冊帳戶
- 驗證網址
- 公錀簽核
# openssl genrsa -des3 -out exmple.com.key 4096
Generating RSA private key, 4096 bit long modulus
................................................................................................................................................................++
...............................................++
e is 65537 (0x10001)
Enter pass phrase for exmple.com.key:
Verifying - Enter pass phrase for exmple.com.key:
從新增的私錀中，產生一個憑證請求檔，並在請求檔中，寫入「目標網址」(也就是你剛驗證過的那個網址)的所屬資料，如：所在地、單位名稱、負責人信箱等：
# openssl req -new -key exmple.com.key -out exmple.com.csr
Enter pass phrase for exmple.com.key:
You are about to be asked to enter information that will be incorporated
into your certificate request.
What you are about to enter is what is called a Distinguished Name or a DN.
There are quite a few fields but you can leave some blank
For some fields there will be a default value,
If you enter '.', the field will be left blank.
-----
Country Name (2 letter code) [AU]:{{TW}}
State or Province Name (full name) [Some-State]:{{Taichung}}
Locality Name (eg, city) []:{{Taichung}}
Organization Name (eg, company) [Internet Widgits Pty Ltd]:{{EXAMPLE-Company}}
Organizational Unit Name (eg, section) []:{{EXAMPLE-Company}}
Common Name (eg, YOUR name) []:{{EXAMPLE Company}}
Email Address []:{{master@exmple.com}}
Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:
然後在 Apache 設定檔中設定如下：
SSLEngine on重新啟動 Apache 時，它會問你私錀密碼為何? 這個動作在管理員面前發生是沒有問題的，但在系統自動重開機時，會造成困惱，所以我們可移除私錀的加密，指令如下：
SSLProtocol all -SSLv2
SSLCipherSuite ALL:!ADH:!EXPORT:!SSLv2:RC4+RSA:+HIGH:+MEDIUM
SSLCertificateFile /etc/apache2/example.com.crt
SSLCertificateKeyFile /etc/apache2/example.com.key
SSLCertificateChainFile /etc/apache2/sub.class1.server.ca.pem
SSLCACertificateFile /etc/apache2/ca.pem
SetEnvIf User-Agent ".*MSIE.*" nokeepalive ssl-unclean-shutdown
# openssl rsa -in exmple.com.key -out exmple.com.key.no_password
exmple.com.key.no_password 這個私錀檔就是沒加密的，將它寫入 apache 設定檔即可。
USN-1107-1: x11-xserver-utils vulnerability
Ubuntu Security Notice USN-1107-1
6th April, 2011
x11-xserver-utils vulnerability
A security issue affects these releases of Ubuntu and its
derivatives:
- Ubuntu 10.10
- Ubuntu 10.04 LTS
- Ubuntu 9.10
- Ubuntu 8.04 LTS
Summary
An attacker could send crafted input to xrdb and cause it to run programs
as root.
Software description
- x11-xserver-utils
- X server utilities
Details
Sebastian Krahmer discovered that the xrdb utility incorrectly filtered
crafted hostnames. An attacker could use this flaw with a malicious
DHCP server or with a remote xdmcp login and execute arbitrary code,
resulting in root privilege escalation.
Update instructions
The problem can be corrected by updating your system to the following
package version:
- Ubuntu 10.10:
x11-xserver-utils
7.5+2ubuntu1.1
- Ubuntu 10.04 LTS:
x11-xserver-utils
7.5+1ubuntu2.1
- Ubuntu 9.10:
x11-xserver-utils
7.4+2ubuntu3.1
- Ubuntu 8.04 LTS:
x11-xserver-utils
7.3+2ubuntu0.1
After a standard system update you need to reboot your computer to make
all the necessary changes.