It was found that a malicious HVM guest administrator can cause DoS, specifically prevent use of physical CPU for significant, perhaps indefinite period. When a benign exception occurs while delivering another benign exception, it is architecturally specified that these would be delivered sequentially. There are, however, cases where this results in an infinite loop inside the CPU, which (in the virtualized case) can be broken only by intercepting delivery of the respective exception.
When a guest sets up a hardware breakpoint covering a data structure involved in delivering #DB (Debug Exception), upon completion of the delivery of the first exception another #DB will need to be delivered. The effects slightly differ depending on further guest characteristics:
Guests running in 32-bit mode would be expected to sooner or later encounter another fault due to the stack pointer decreasing during each iteration of the loop. The most likely case would be #PF (Page Fault) due to running into unmapped virtual space. However, an infinite loop cannot be excluded (e.g. when the guest is running with paging disabled).
Guests running in long mode, but not using the IST (Interrupt Stack Table) feature for the IDT entry corresponding to #DB would behave similarly to guests running in 32-bit mode, just that the larger virtual address space allows for a much longer loop. The loop can't, however, be infinite, as eventually the stack pointer would move into non-canonical address space, causing #SS (Stack Fault) instead.
Guests running in long mode and using the IST for the IDT entry corresponding to #DB would enter an infinite loop, as the stack pointer wouldn't change between #DB instances.
If a host watchdog (Xen or dom0) is in use, this can lead to a watchdog timeout and consequently a reboot of the host. If another, innocent, guest, is configured with a watchdog, this issue can lead to a reboot of such a guest.
A privileged user inside guest could use this flaw to crash the host kernel resulting in DoS.
For KVM virtualisation, it only affects the AMD processor support, as for Intel it already intercepts the #DB exception.
Upstream KVM patch: ------------------- -> http://permalink.gmane.org/gmane.linux.kernel/2082332
References: ----------- -> http://www.openwall.com/lists/oss-security/2015/11/10/1
Integer signedness issues were discovered in IndicRearrangementProcessor and IndicRearrangementProcessor2 in the ICU Layout Engine. A specially crafted font file could cause an application using ICU to parse untrusted fonts to crash and, possibly, execute arbitrary code.
ICU code is embedded the 2D component in OpenJDK and used by FontManager. An untrusted Java application or applet could use this flaw to execute arbitrary code with Java Virtual Machine privileges and bypass Java sandbox restrictions.
It was discovered that the JPEG decoder in the AWT component of OpenJDK did not use correct buffer boundary in certain cases when decoding JPEG files. A specially crafted JPEG file could cause a Java application to corrupt its memory and possibly execute arbitrary code when opened. An untrusted Java application or applet could also use this flaw to bypass Java sandbox restrictions.
It was discovered that the JAXP component of OpenJDK did not properly count total size of the expanded general entities and therefore did not properly enforce the totalEntitySizeLimit limit. An attacker able to make a Java application parse a specially crafted XML file could use this flaw to make the application use and excessive amount of memory and possibly exit on out of memory condition.
JAXP XML parsing limits are described on the following page:
https://docs.oracle.com/javase/tutorial/jaxp/limits/limits.html
It was discovered that the RMIConnector and RMIConnectionImpl classes in the JMX component of OpenJDK could log sensitive information such as user passwords in its debug log, possibly leading the exposure of the information.
A flaw was found in the deserialization of the URL class in the Networking component of OpenJDK. Deserialization of the specially crafted data could result in creation of the URL object with an inconsistent state. An untrusted Java application or applet could use this flaw to bypass certain Java sandbox restrictions.
A flaw was found in the way TLS 1.2 could use the MD5 hash function for signing ServerKeyExchange and Client Authentication packets during a TLS handshake. A man-in-the-middle attacker able to force a TLS connection to use the MD5 hash function could use this flaw to conduct collision attacks to impersonate a TLS server or an authenticated TLS client.
Buffer overflow vulnerabilities in functions pnggetPLTE/pngsetPLTE, allowing remote attackers to cause DoS to application or have unspecified other impact. These functions failed to check for an out-of-range palette when reading or writing PNG files with a bitdepth less than 8. Some applications might read the bit depth from the IHDR chunk and allocate memory for a 2^N entry palette, while libpng can return a palette with up to 256 entries even when the bit depth is less than 8.
Affected versions of libpng are before 1.0.64, 1.1.x and 1.2.x before 1.2.54, 1.3.x and 1.4.x before 1.4.17, 1.5.x before 1.5.24, and 1.6.x before 1.6.19.
Upstream patches:
https://github.com/glennrp/libpng/commit/81f44665cce4cb1373f049a76f3904e981b7a766 https://github.com/glennrp/libpng/commit/a901eb3ce6087e0afeef988247f1a1aa208cb54d https://github.com/glennrp/libpng/commit/1bef8e97995c33123665582e57d3ed40b57d5978 https://github.com/glennrp/libpng/commit/83f4c735c88e7f451541c1528d8043c31ba3b466 https://github.com/glennrp/libpng/commit/9f2ad4928e47036cf1ac9b8fe45a491f15be2324
CVE assignment:
http://seclists.org/oss-sec/2015/q4/264
Last updated 15 January 2025
bdf/bdflib.c in FreeType before 2.5.4 identifies property names by only verifying that an initial substring is present, which allows remote attackers to discover heap pointer values and bypass the ASLR protection mechanism via a crafted BDF font.
It was reported that possible use-after-free vulnerability in keyring facility, possibly leading to local privilege escalation, was found. Function joinsessionkeyring in security/keys/processkeys.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.
Introduced by: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=3a50597de8635cd05133bd12c95681c82fe7b878
References: http://perception-point.io/2016/01/14/analysis-and-exploitation-of-a-linux-kernel-vulnerability-cve-2016-0728/
Red Hat KCS article: https://access.redhat.com/articles/2131021
Upstream patch: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=23567fd052a9abb6d67fe8e7a9ccdd9800a540f2
Heap-based buffer overflow in wpasupplicant 1.0 through 2.4 allows remote attackers to cause a denial of service (crash), read memory, or possibly execute arbitrary code via crafted SSID information in a management frame when creating or updating P2P entries.
A flaw was found in the way the Linux kernel's networking implementation handled UDP packets with incorrect checksum values. A remote attacker could potentially use this flaw to trigger an infinite loop in the kernel, resulting in a denial of service on the system, or cause a denial of service in applications using the edge triggered epoll functionality.
Integer overflow in the sgstartreq function in drivers/scsi/sg.c in the Linux kernel 2.6.x through 4.x before 4.1 allows local users to cause a denial of service or possibly have unspecified other impact via a large iovcount value in a write request.
Apache Commons HttpClient 3.x, as used in Amazon Flexible Payments Service (FPS) merchant Java SDK and other products, does not verify that the server hostname matches a domain name in the subject's Common Name (CN) or subjectAltName field of the X.509 certificate, which allows man-in-the-middle attackers to spoof SSL servers via an arbitrary valid certificate.
An out-of-bounds read in pngconverttorfc1123 in png.c was found.
Upstream bug:
http://sourceforge.net/p/libpng/bugs/241/
Upstream patch:
http://sourceforge.net/p/libpng/code/ci/fbf0f024346ca0a4ffc64b082a95c6b6bb6d29c4/
CVE assignment:
http://seclists.org/oss-sec/2015/q4/161
Buffer overflow in the afReadFrames function in audiofile (aka libaudiofile and Audio File Library) allows user-assisted remote attackers to cause a denial of service (program crash) or possibly execute arbitrary code via a crafted audio file, as demonstrated by sixteen-stereo-to-eight-mono.c.
Info-ZIP UnZip 6.0 allows remote attackers to cause a denial of service (infinite loop) via empty bzip2 data in a ZIP archive.
Info-ZIP UnZip 6.0 allows remote attackers to cause a denial of service (heap-based buffer over-read and application crash) or possibly execute arbitrary code via a crafted password-protected ZIP archive possibly related to an Extra-Field size value.
Moxilla Firefox allows remote attackers to bypass the Same Origin Policy to read arbitrary files or gain privileges.
An unspecified flaw was found in the Libraries component in OpenJDK. ObjectInputStream's readSerialData() could, in certain cases, incorrectly perform deserialization of data from serialized input. An untrusted Java application or applet could use this flaw to bypass Java sandbox restrictions.
nbd-server in Network Block Device (nbd) before 3.5 does not properly check IP addresses, which might allow remote attackers to bypass intended access restrictions via an IP address that has a partial match in the authfile configuration file.
The pngpushreadzTXt function in pngpread.c in libpng 1.0.x before 1.0.58, 1.2.x before 1.2.48, 1.4.x before 1.4.10, and 1.5.x before 1.5.10 allows remote attackers to cause a denial of service (out-of-bounds read) via a large availin field value in a PNG image.
It was discovered that the Invariance Weakness of the RC4 stream cipher could be used to recover plaintext from a TLS connection, when RC4 encryption is used.
"The Invariance Weakness is an L-shape key pattern in RC4 keys, which once it exists in an RC4 key, preserves part of the state permutation intact throughout the initialization process. This intact part includes the least significant bits of the permutation, when processed by the PRGA algorithm, determines the least significant bits of the allegedly pseudo-random output stream along a long prefix of the stream."
This can lead to significant leakage of plaintext bytes from the ciphertext.
External Reference:
http://www.imperva.com/docs/HIIAttackingSSLwhenusingRC4.pdf
Last updated 24 July 2024
Apache HTTP Server 2.4.16 release fixes the following issue:
) SECURITY: CVE-2015-3185 (cve.mitre.org) Replacement of apsomeauthrequired (unusable in Apache httpd 2.4) with new apsomeauthnrequired and apforceauthn hook. [Ben Reser]
External References:
http://httpd.apache.org/security/vulnerabilities24.html#2.4.16
click/install.py in click does not require files in package filesystem tarballs to start with ./ (dot slash), which allows remote attackers to install an alternate security policy and gain privileges via a crafted package, as demonstrated by the test.mmrow app for Ubuntu phone.
sosreport in Red Hat sos 1.7 and earlier on Red Hat Enterprise Linux (RHEL) 5 produces an archive with an fstab file potentially containing cleartext passwords, and lacks a warning about reviewing this archive to detect included passwords, which might allow remote attackers to obtain sensitive information by leveraging access to a technical-support data stream.
The GIF decoder in QtGui in Qt before 5.3 allows remote attackers to cause a denial of service (NULL pointer dereference) via invalid width and height values in a GIF image.
Last updated 24 July 2024