-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 - ------------------------------------------------------------------------- Debian Security Advisory DSA-4120-1 security@debian.org https://www.debian.org/security/ Yves-Alexis Perez February 22, 2018 https://www.debian.org/security/faq - ------------------------------------------------------------------------- Package : linux CVE ID : CVE-2017-5715 CVE-2017-5754 CVE-2017-13166 CVE-2018-5750 Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks. CVE-2017-5715 Multiple researchers have discovered a vulnerability in various processors supporting speculative execution, enabling an attacker controlling an unprivileged process to read memory from arbitrary addresses, including from the kernel and all other processes running on the system. This specific attack has been named Spectre variant 2 (branch target injection) and is mitigated in the Linux kernel for the Intel x86-64 architecture by using the 'retpoline' compiler feature which allows indirect branches to be isolated from speculative execution. CVE-2017-5754 Multiple researchers have discovered a vulnerability in Intel processors, enabling an attacker controlling an unprivileged process to read memory from arbitrary addresses, including from the kernel and all other processes running on the system. This specific attack has been named Meltdown and is addressed in the Linux kernel on the powerpc/ppc64el architectures by flushing the L1 data cache on exit from kernel mode to user mode (or from hypervisor to kernel). This works on Power7, Power8 and Power9 processors. CVE-2017-13166 A bug in the 32-bit compatibility layer of the v4l2 IOCTL handling code has been found. Memory protections ensuring user-provided buffers always point to userland memory were disabled, allowing . This bug could be exploited by an attacker to overwrite kernel memory from an unprivileged userland process, leading to privilege escalation. CVE-2018-5750 An information leak has been found in the Linux kernel. The acpi_smbus_hc_add() prints a kernel address in the kernel log at every boot, which could be used by an attacker on the system to defeat kernel ASLR. Additionnaly to those vulnerability, some mitigations for CVE-2017-5753 are included in this release. CVE-2017-5753 Multiple researchers have discovered a vulnerability in various processors supporting speculative execution, enabling an attacker controlling an unprivileged process to read memory from arbitrary addresses, including from the kernel and all other processes running on the system. This specific attack has been named Spectre variant 1 (bounds-check bypass) and is mitigated in the Linux kernel architecture by identifying vulnerable code sections (array bounds checking followed by array access) and replacing the array access with the speculation-safe array_index_nospec() function. More use sites will be added over time. For the stable distribution (stretch), these problems have been fixed in version 4.9.82-1+deb9u2. We recommend that you upgrade your linux packages. For the detailed security status of linux please refer to its security tracker page at: https://security-tracker.debian.org/tracker/linux Further information about Debian Security Advisories, how to apply these updates to your system and frequently asked questions can be found at: https://www.debian.org/security/ Mailing list: debian-security-announce@lists.debian.org -----BEGIN PGP SIGNATURE----- iQEzBAEBCgAdFiEE8vi34Qgfo83x35gF3rYcyPpXRFsFAlqO5kYACgkQ3rYcyPpX RFtjkgf9HK7sq/xNOFjZsc3iaVNdzDhDEth8ql/Q9WsbDP9JmlrwmlTsD/QAgXgx m9zIIJzyI9Dry60bVvYZHFrtYhQXX5zp9DYa89oinHv+1UxzaYHTHsNoh326k86n QUcDLYe2+JJgi/2KjLqfFfa5zgMqUNj3C6iBDezs0tCfE/QZAmAX7aA7A3mTJYLB 3v2tSoEeW0fb9M5Ic2QHJD1TW6NU+j6zaUeJRyhj7lthmyOcNxwTIrt2CswDnLUI tCMtzdce6OWAW5xXQxHwzzf5+vRvmm/f+wM2V3WTcA1Q0tfA5cZGFe2SMOhyGKtf KG1ziLYIY0OdCtdxj0K/wEzpe6cikg== =B81o -----END PGP SIGNATURE-----