January 2016 - Arch-security - lists.archlinux.org

[arch-security] [ASA-201601-24] python2-rsa: signature forgery
by Levente Polyak 25 Jan '16

25 Jan '16

Arch Linux Security Advisory ASA-201601-24 ========================================== Severity: Medium Date : 2016-01-25 CVE-ID : CVE-2016-1494 Package : python2-rsa Type : signature forgery Remote : Yes Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package python2-rsa before version 3.3-1 is vulnerable to signature forgery. Resolution ========== Upgrade to 3.3-1. # pacman -Syu "python2-rsa>=3.3-1" The problem has been fixed upstream in version 3.3. Workaround ========== None. Description =========== The verify function in the RSA package for Python (Python-RSA) before 3.3 allows attackers to spoof signatures with a small public exponent via crafted signature padding, aka a BERserk attack. Impact ====== A remote attacker is able to spoof certain signatures via crafted signature padding. References ========== https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-1494 https://blog.filippo.io/bleichenbacher-06-signature-forgery-in-python-rsa/ https://bitbucket.org/sybren/python-rsa/pull-requests/14/security-fix-bb06-…

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[arch-security] [ASA-201601-23] python-rsa: signature forgery
by Levente Polyak 25 Jan '16

25 Jan '16

Arch Linux Security Advisory ASA-201601-23 ========================================== Severity: Medium Date : 2016-01-25 CVE-ID : CVE-2016-1494 Package : python-rsa Type : signature forgery Remote : Yes Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package python-rsa before version 3.3-1 is vulnerable to signature forgery. Resolution ========== Upgrade to 3.3-1. # pacman -Syu "python-rsa>=3.3-1" The problem has been fixed upstream in version 3.3. Workaround ========== None. Description =========== The verify function in the RSA package for Python (Python-RSA) before 3.3 allows attackers to spoof signatures with a small public exponent via crafted signature padding, aka a BERserk attack. Impact ====== A remote attacker is able to spoof certain signatures via crafted signature padding. References ========== https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-1494 https://blog.filippo.io/bleichenbacher-06-signature-forgery-in-python-rsa/ https://bitbucket.org/sybren/python-rsa/pull-requests/14/security-fix-bb06-…

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[arch-security] [ASA-201601-22] libdwarf: denial of service
by Levente Polyak 21 Jan '16

21 Jan '16

Arch Linux Security Advisory ASA-201601-22 ========================================== Severity: Low Date : 2016-01-21 CVE-ID : CVE-2015-8750 Package : libdwarf Type : denial of service Remote : No Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package libdwarf before version 20160115-1 is vulnerable to denial of service. Resolution ========== Upgrade to 20160115-1. # pacman -Syu "libdwarf>=20160115-1" The problem has been fixed upstream in version 20160115. Workaround ========== None. Description =========== A problem has been discovered when the debug_abbrev section is marked as NOBITS in the ELF file - in other words as a zero-init section rather than a section with contents in the file. Such a crafted section is leading to a null pointer dereference resulting in denial of service. Impact ====== A local attacker is able to create a specially crafted file with zero-init section that, when processed, is leading to a denial of service. References ========== https://access.redhat.com/security/cve/CVE-2015-8750 https://bugzilla.redhat.com/show_bug.cgi?id=1294264 https://github.com/tomhughes/libdwarf/commit/11750a2838e

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[arch-security] [ASA-201601-21] bind: denial of service
by Levente Polyak 21 Jan '16

21 Jan '16

Arch Linux Security Advisory ASA-201601-21 ========================================== Severity: High Date : 2016-01-21 CVE-ID : CVE-2015-8704 CVE-2015-8705 Package : bind Type : denial of service Remote : Yes Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package bind before version 9.10.3.P3-1 is vulnerable to denial of service. Resolution ========== Upgrade to 9.10.3.P3-1. # pacman -Syu "bind>=9.10.3.P3-1" The problems have been fixed upstream in version 9.10.3.P3. Workaround ========== None. Description =========== - CVE-2015-8704 (denial of service) A buffer size check used to guard against overflow could cause named to exit with an INSIST failure In apl_42.c. A server could exit while performing certain string formatting operations. Examples include (but may not be limited to): 1) Slaves using text-format db files could be vulnerable if receiving a malformed record in a zone transfer from their master. 2) Masters using text-format db files could be vulnerable if they accept a malformed record in a DDNS update message. 3) Recursive resolvers are potentially vulnerable when debug logging, if they are fed a deliberately malformed record by a malicious server. 4) A server which has cached a specially constructed record could encounter this condition while performing 'rndc dumpdb'. - CVE-2015-8705 (denial of service) In versions of BIND 9.10, errors can occur when OPT pseudo-RR data or ECS options are formatted to text. In 9.10.3 through 9.10.3-P2, the issue may result in a REQUIRE assertion failure in buffer.c resulting in application exit. This issue can affect both authoritative and recursive servers if they are performing debug logging. It may also crash related tools which use the same code, such as dig or delv. Impact ====== A remote attacker is able to use specially crafted records that, when processed, are leading to application crash resulting in denial of service. This issue affects slaves, masters, recursive resolvers as well as related tools which use the same code. References ========== https://access.redhat.com/security/cve/CVE-2015-8704 https://access.redhat.com/security/cve/CVE-2015-8705 https://kb.isc.org/article/AA-01335 https://kb.isc.org/article/AA-0133

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[arch-security] [ASA-201601-20] linux: privilege escalation
by Levente Polyak 20 Jan '16

20 Jan '16

Arch Linux Security Advisory ASA-201601-20 ========================================== Severity: Critical Date : 2016-01-20 CVE-ID : CVE-2016-0728 Package : linux Type : privilege escalation Remote : No Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package linux before version 4.3.3-3 is vulnerable to local privilege escalation. Resolution ========== Upgrade to 4.3.3-3. # pacman -Syu "linux>=4.3.3-3" The problem has been fixed upstream but no release is available yet. Workaround ========== None. Description =========== It was reported that possible use-after-free vulnerability in keyring facility, possibly leading to local privilege escalation, was found. Function join_session_keyring in security/keys/process_keys.c holds a reference to the requested keyring, but if that keyring is the same as the one being currently used by the process, the kernel wouldn't decrease keyring->usage before returning to userspace. The usage field can be possibly overflowed causing use-after-free on the keyring object. Impact ====== A local attacker is able to make use of this vulnerability to elevate privileges and gain root access to the underlying system. References ========== https://access.redhat.com/security/cve/CVE-2016-0728 http://perception-point.io/2016/01/14/analysis-and-exploitation-of-a-linux-… https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=… https://bugs.archlinux.org/task/47820

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[arch-security] [ASA-201601-19] ntp: time alteration
by Remi Gacogne 17 Jan '16

17 Jan '16

Arch Linux Security Advisory ASA-201601-19 ========================================== Severity: Medium Date : 2016-01-17 CVE-ID : CVE-2015-5300 Package : ntp Type : time alteration Remote : Yes Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package ntp before version 4.2.8.p5-1 is vulnerable to time alteration. Resolution ========== Upgrade to 4.2.8.p5-1. # pacman -Syu "ntp>=4.2.8.p5-1" The problem has been fixed upstream in version 4.2.8.p5. Workaround ========== Removing -g from the ntpd startup options limits the time modification to 900s per attack. This can be done by editing the ExecStart line of the /usr/lib/systemd/system/ntpd.service file to remove the -g option, then issuing: # systemctl daemon-reload # systemctl restart ntpd Description =========== If ntpd is always started with the -g option, which is common and against long-standing recommendation, and if at the moment ntpd is restarted an attacker can immediately respond to enough requests from enough sources trusted by the target, which is difficult and not common, there is a window of opportunity where the attacker can cause ntpd to set the time to an arbitrary value. Similarly, if an attacker is able to respond to enough requests from enough sources trusted by the target, the attacker can cause ntpd to abort and restart, at which point it can tell the target to set the time to an arbitrary value if and only if ntpd was re-started against long-standing recommendation with the -g flag, or if ntpd was not given the -g flag, the attacker can move the target system's time by at most 900 seconds' time per attack. Impact ====== As the ntpd default startup options on Arch contain -g, a remote attacker might be able to alter the system time to an arbitrary value, bypassing checks based on the time, like for example X.509 certificates expiration dates. References ========== https://access.redhat.com/security/cve/CVE-2015-5300 http://support.ntp.org/bin/view/Main/NtpBug2956 https://www.cs.bu.edu/~goldbe/NTPattack.html

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[arch-security] [ASA-201601-18] roundcubemail: remote code execution
by Remi Gacogne 17 Jan '16

17 Jan '16

Arch Linux Security Advisory ASA-201601-18 ========================================== Severity: High Date : 2016-01-17 CVE-ID : CVE-2015-8770 Package : roundcubemail Type : remote code execution Remote : Yes Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package roundcubemail before version 1.2beta-2 is vulnerable to remote code execution. Resolution ========== Upgrade to 1.2beta-2. # pacman -Syu "roundcubemail>=1.2beta-2" The problem has been fixed upstream in version 1.0.8 and 1.1.4. Workaround ========== None. Description =========== High-Tech Bridge Security Research Lab discovered a path traversal vulnerability in Roundcube. Vulnerability can be exploited to gain access to sensitive information and under certain circumstances to execute arbitrary code and totally compromise the vulnerable server. The vulnerability exists due to insufficient sanitization of "_skin" HTTP POST parameter in "/index.php" script when changing between different skins of the web application. A remote authenticated attacker can use path traversal sequences (e.g. "../../") to load a new skin from arbitrary location on the system, readable by the webserver. Exploitation of the vulnerability requires valid user credentials and ability to create files on vulnerable host. Impact ====== A remote authenticated attacker can access sensitive information and may be able to execute arbitrary code on the affected host. References ========== https://bugs.archlinux.org/task/47764 https://www.htbridge.com/advisory/HTB23283 https://access.redhat.com/security/cve/CVE-2015-8770 https://roundcube.net/news/2015/12/26/updates-1.1.4-and-1.0.8-released/ https://github.com/roundcube/roundcubemail/commit/10e5192a2b1bc90ec137f5e69…

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[arch-security] [ASA-201601-17] ffmpeg: information leakage
by Remi Gacogne 17 Jan '16

17 Jan '16

Arch Linux Security Advisory ASA-201601-17 ========================================== Severity: Medium Date : 2016-01-17 CVE-ID : CVE-2016-1897 CVE-2016-1898 Package : ffmpeg Type : information leakage Remote : Yes Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package ffmpeg before version 1:2.8.4-3 is vulnerable to information leakage. Resolution ========== Upgrade to 1:2.8.4-3. # pacman -Syu "ffmpeg>=1:2.8.4-3" The problem has been fixed upstream in version 2.8.5. Workaround ========== None. Description =========== A vulnerability in the way FFmpeg handles the concat (CVE-2016-1897) and subfile (CVE-2016-1898) protocols in a HTTP Live Streaming (HLS) M3U8 file allows a remote attacker to conduct a cross-origin attacks, and to access arbitrary local files on the vulnerable host. The attack uses a crafted M3U8 file to make FFmpeg send a HTTP request to an external server, with the URL containing data from arbitrary local files. Impact ====== A remote attacker, by providing a crafted M3U8 file, can access the content of arbitrary local files on the affected host. References ========== https://bugs.archlinux.org/task/47738 http://seclists.org/oss-sec/2016/q1/85 https://security-tracker.debian.org/tracker/CVE-2016-1897 https://security-tracker.debian.org/tracker/CVE-2016-1898

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[arch-security] [ASA-201601-16] syncthing: information leakage
by Levente Polyak 17 Jan '16

17 Jan '16

Arch Linux Security Advisory ASA-201601-16 ========================================== Severity: High Date : 2016-01-17 CVE-ID : CVE-2015-8618 Package : syncthing Type : information leakage Remote : Yes Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package syncthing before version 0.12.14-2 is vulnerable to information leakage. Resolution ========== Upgrade to 0.12.14-2. # pacman -Syu "syncthing>=0.12.14-2" The problem has been fixed upstream in go version 1.5.3. Workaround ========== None. Description =========== This issue can affect RSA computations in crypto/rsa, which is used by crypto/tls. TLS servers on 32-bit systems could plausibly leak their RSA private key due to this issue. Other protocol implementations that create many RSA signatures could also be impacted in the same way. Specifically, incorrect results in one part of the RSA Chinese Remainder computation can cause the result to be incorrect in such a way that it leaks one of the primes. While RSA blinding should prevent an attacker from crafting specific inputs that trigger the bug, on 32-bit systems the bug can be expected to occur at random around one in 2^26 times. Thus collecting around 64 million signatures (of known data) from an affected server should be enough to extract the private key used. On 64-bit systems, the frequency of the bug is so low (less than one in 2^50) that it would be very difficult to exploit. Nonetheless, everyone is strongly encouraged to upgrade. Impact ====== A remote unauthenticated attacker can extract a private RSA key by passively collecting signatures. References ========== https://access.redhat.com/security/cve/CVE-2015-8618 https://groups.google.com/forum/#!topic/golang-dev/MEATuOi_ei4 https://lists.archlinux.org/pipermail/arch-security/2016-January/000516.html

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[arch-security] [ASA-201601-15] keybase: information leakage
by Levente Polyak 17 Jan '16

17 Jan '16

Arch Linux Security Advisory ASA-201601-15 ========================================== Severity: High Date : 2016-01-17 CVE-ID : CVE-2015-8618 Package : keybase Type : information leakage Remote : Yes Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package keybase before version 1.0.8.0-2 is vulnerable to information leakage. Resolution ========== Upgrade to 1.0.8.0-2. # pacman -Syu "keybase>=1.0.8.0-2" The problem has been fixed upstream in go version 1.5.3. Workaround ========== None. Description =========== This issue can affect RSA computations in crypto/rsa, which is used by crypto/tls. TLS servers on 32-bit systems could plausibly leak their RSA private key due to this issue. Other protocol implementations that create many RSA signatures could also be impacted in the same way. Specifically, incorrect results in one part of the RSA Chinese Remainder computation can cause the result to be incorrect in such a way that it leaks one of the primes. While RSA blinding should prevent an attacker from crafting specific inputs that trigger the bug, on 32-bit systems the bug can be expected to occur at random around one in 2^26 times. Thus collecting around 64 million signatures (of known data) from an affected server should be enough to extract the private key used. On 64-bit systems, the frequency of the bug is so low (less than one in 2^50) that it would be very difficult to exploit. Nonetheless, everyone is strongly encouraged to upgrade. Impact ====== A remote unauthenticated attacker can extract a private RSA key by passively collecting signatures. References ========== https://access.redhat.com/security/cve/CVE-2015-8618 https://groups.google.com/forum/#!topic/golang-dev/MEATuOi_ei4 https://lists.archlinux.org/pipermail/arch-security/2016-January/000516.html

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