A flaw was found in the KVM's AMD code for supporting SVM nested virtualization. The flaw occurs when processing the VMCB (virtual machine control block) provided by the L1 guest to spawn/handle a nested guest (L2). Due to improper validation of the "virtext" field, this issue could allow a malicious L1 to disable both VMLOAD/VMSAVE intercepts and VLS (Virtual VMLOAD/VMSAVE) for the L2 guest. As a result, the L2 guest would be allowed to read/write physical pages of the host, resulting in a crash of the entire system, leak of sensitive data or potential guest-to-host escape.
A flaw was found in grub2 in versions prior to 2.06. The cutmem command does not honor secure boot locking allowing an privileged attacker to remove address ranges from memory creating an opportunity to circumvent SecureBoot protections after proper triage about grub's memory layout. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
A flaw was found in grub2 in versions prior to 2.06. Variable names present are expanded in the supplied command line into their corresponding variable contents, using a 1kB stack buffer for temporary storage, without sufficient bounds checking. If the function is called with a command line that references a variable with a sufficiently large payload, it is possible to overflow the stack buffer, corrupt the stack frame and control execution which could also circumvent Secure Boot protections. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
A flaw was found in grub2 in versions prior to 2.06. During USB device initialization, descriptors are read with very little bounds checking and assumes the USB device is providing sane values. If properly exploited, an attacker could trigger memory corruption leading to arbitrary code execution allowing a bypass of the Secure Boot mechanism. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
A flaw was found in grub2 in versions prior to 2.06. The rmmod implementation allows the unloading of a module used as a dependency without checking if any other dependent module is still loaded leading to a use-after-free scenario. This could allow arbitrary code to be executed or a bypass of Secure Boot protections. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
A flaw was found in grub2 in versions prior to 2.06, where it incorrectly enables the usage of the ACPI command when Secure Boot is enabled. This flaw allows an attacker with privileged access to craft a Secondary System Description Table (SSDT) containing code to overwrite the Linux kernel lockdown variable content directly into memory. The table is further loaded and executed by the kernel, defeating its Secure Boot lockdown and allowing the attacker to load unsigned code. The highest threat from this vulnerability is to data confidentiality and integrity, as well as system availability.
BSD mailx 8.1.2 and earlier allows remote attackers to execute arbitrary commands via a crafted email address.
Apache Xerces-C could allow a remote attacker to execute arbitrary code on the system, caused by an use-after-free error during the scanning of external DTDs. By sending a specially crafted file, an attacker could exploit this vulnerability to execute arbitrary code or cause a denial of service condition on the system.
In ghostscript before version 9.50, the .buildfont1 procedure did not properly secure its privileged calls, enabling scripts to bypass -dSAFER restrictions. An attacker could abuse this flaw by creating a specially crafted PostScript file that could escalate privileges and access files outside of restricted areas.
A flaw was found in the "Leaf and Chain" OCSP policy implementation in JSS' CryptoManager versions after 4.4.6, 4.5.3, 4.6.0, where it implicitly trusted the root certificate of a certificate chain. Applications using this policy may not properly verify the chain and could be vulnerable to attacks such as Man in the Middle.
It was discovered that the Kerberos client implementation in the Libraries component of OpenJDK used the sname field from the plain text part rather than encrypted part of the KDC reply. A man-in-the-middle attacker could possibly use this flaw to impersonate Kerberos services to Java applications acting as Kerberos clients.
An attacker within bluetooth transmission range can cause a stack buffer overflow in the Bluetooth system of the Linux kernel while processing pending L2CAP configuration responses from a client. An unauthenticated user able to connect to a system via Bluetooth could use this flaw to potentially execute arbitrary code with root privileges on the system.
External References:
https://www.armis.com/blueborne/ https://access.redhat.com/security/vulnerabilities/blueborne https://access.redhat.com/solutions/3177231 https://access.redhat.com/blogs/product-security/posts/blueborne
An upstream patch:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e860d2c904d1a9f38a24eb44c9f34b8f915a6ea3
The cryptoxmit function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (crash). NOTE: This vulnerability exists due to an incomplete fix for CVE-2014-9750.
The "pidfile" or "driftfile" directives in NTP ntpd 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77, when ntpd is configured to allow remote configuration, allows remote attackers with an IP address that is allowed to send configuration requests, and with knowledge of the remote configuration password to write to arbitrary files via the :config command.
It was discovered that the Nashorn JavaScript engine in the Scripting component of OpenJDK could allow JavaScripts to access Java APIs even when access to Java APIs was disabled. An untrusted JavaScript executed by Nashorn could use this flaw to bypass intended restrictions.
A covert timing channel flaw was found in the DSA implementation in the JCE component of OpenJDK. A remote attacker able to make a Java application generate DSA signatures on demand could possibly use this flaw to extract certain information about the used key via a timing side channel.
Note that the fix for this issue reverts the fix for CVE-2016-5548 (see bug 1413920) and uses different approach to implement blinding of the DSA operations.
It was discovered that the LDAPCertStore class in the Security component of OpenJDK followed LDAP referrals to arbitrary URLs. A specially-crafted LDAP referral URL could cause LDAPCertStore to communicate with non-LDAP servers.
It was discovered that the JAR (Java ARchive) verifier in the Security component of OpenJDK did not correctly handle files inside archives with missing digest. An attacker could possibly use this flaw to manipulate content of a singed JAR, bypassing intended verification.
It was discovered that the Hotspot component of OpenJDK did not properly check for integer overflows when generating range check loop predicates. An untrusted Java application or applet could use this flaw to corrupt JVM memory and cause it to crash or, possibly, execute arbitrary code, bypassing Java sandbox restrictions.
An FR-GV-201 issue in FreeRADIUS 2.x before 2.2.10 and 3.x before 3.0.15 allows "Read / write overflow in makesecret()" and a denial of service.
A vulnerability was found in icoutils in extract.c. It is possible to access unallocated memory via wrestool while parsing maliciously crafted file which would make the application crash or possibly allow code execution.
References:
http://seclists.org/oss-sec/2017/q1/56
Upstream patch:
http://git.savannah.gnu.org/cgit/icoutils.git/commit/?id=1aa9f28f7bcbdfff6a84a15ac8d9a87559b1596a
An integer overflow vulnerability was found in extract.c while transferring resources into file memory. A maliciously crafted file could make the application crash or possibly allow code execution.
References:
http://seclists.org/oss-sec/2017/q1/56
Upstream patch:
http://git.savannah.gnu.org/cgit/icoutils.git/commit/?id=1a108713ac26215c7568353f6e02e727e6d4b24a
A malformed query response received by a recursive server in response to a query of RTYPE ANY could trigger an assertion failure while named is attempting to add the RRs in the query response to the cache. While the combination of properties which triggers the assertion should not occur in normal traffic, it is potentially possible for the assertion to be triggered deliberately by an attacker sending a specially-constructed answer having the required properties, after having engineered a scenario whereby an ANY query is sent to the recursive server for the target QNAME. A recursive server will itself only send a query of type ANY if it receives a client query of type ANY for a QNAME for which it has no RRsets at all in cache, otherwise it will respond to the client with the the RRsets that it has available.
This vulnerability occurs during the processing of an answer packet received in response to a query. As a result, recursive servers are at the greatest risk; authoritative servers are at risk only to the extent that they perform a limited set of queries.
This description is borrowed from the upstream advisory.
A defect in BIND's handling of responses containing a DNAME answer can cause a resolver to exit after encountering an assertion failure in db.c or resolver.c
During processing of a recursive response that contains a DNAME record in the answer section, BIND can stop execution after encountering an assertion error in resolver.c (error message: "INSIST((valoptions & 0x0002U) != 0) failed") or db.c (error message: "REQUIRE(targetp != ((void )0) && targetp == ((void )0)) failed").
A server encountering either of these error conditions will stop, resulting in denial of service to clients. The risk to authoritative servers is minimal; recursive servers are chiefly at risk.
Integer overflow in the opjpicreatedecode function in pi.c in OpenJPEG allows remote attackers to execute arbitrary code via a crafted JP2 file, which triggers an out-of-bounds read or write.
It was discovered that the Tomcat packages installed configuration file /usr/lib/tmpfiles.d/tomcat.conf writeable to the tomcat group. A member of the group or a malicious web application deployed on Tomcat could use this flaw to escalate their privileges.
Heap-based buffer overflow in the iscsiaioioctl function in block/iscsi.c in QEMU allows local guest OS users to cause a denial of service (QEMU process crash) or possibly execute arbitrary code via a crafted iSCSI asynchronous I/O ioctl call.
Qemu emulator built with VGA emulation with VESA BIOS Extensions(VBE) support is vulnerable to an OOB r/w access issue. It could occur while doing VGA r/w operations via i/o port methods.
A privileged guest user could use this flaw to potentially execute arbitrary code, with privileges of the Qemu process on the host.
Upstream patch: --------------- -> https://lists.gnu.org/archive/html/qemu-devel/2016-05/msg01197.html
Reference: ---------- -> http://www.openwall.com/lists/oss-security/2016/05/09/3
The netchecksumcalculate function in net/checksum.c in QEMU allows local guest OS users to cause a denial of service (out-of-bounds heap read and crash) via the payload length in a crafted packet.
A vulnerability in sosreport was reported, allowing a privilege escalation to unprivileged attacker on RHEL-6, and change the owner and content of certain files on RHEL-7.
sosreport creates temporary directory in /tmp with predictable name sosreport-$hostname-$date with permissions set to 700. Then it creates a tar file with the aforementioned name + .tar suffix. Further it invokes open() with no ONOFOLLOW nor OEXCL set, which can be exploited by placing a file or a symlink in its place.
Attacker can create his own file to steal the content or can create a symlink to create/modify arbitrary files. On RHEL-7, there is fs.protectedsymlinks sysctl provided, which closes this vector. With the setting target of the symlink must match symlink's owner. On RHEL-6 this feature is missing, so the attacker is able to modify arbitrary files and escalate privileges.