Threat Intelligence

The groonga-httpd package 6.1.5-1 for Debian sets the /var/log/groonga ownership to the groonga account, which might let local users obtain root access because of unsafe interaction with logrotate. For example, an attacker can exploit a race condition to insert a symlink from /var/log/groonga/httpd to /etc/bash_completion.d. NOTE: this is an issue in the Debian packaging of the Groonga HTTP server.

Debian tmpreaper version 1.6.13+nmu1 has a race condition when doing a (bind) mount via rename() which could result in local privilege escalation. Mounting via rename() could potentially lead to a file being placed elsewhereon the filesystem hierarchy (e.g. /etc/cron.d/) if the directory being cleaned up was on the same physical filesystem. Fixed versions include 1.6.13+nmu1+deb9u1 and 1.6.14.

A statement in the System Programming Guide of the Intel 64 and IA-32 Architectures Software Developer's Manual (SDM) was mishandled in the development of some or all operating-system kernels, resulting in unexpected behavior for #DB exceptions that are deferred by MOV SS or POP SS, as demonstrated by (for example) privilege escalation in Windows, macOS, some Xen configurations, or FreeBSD, or a Linux kernel crash. The MOV to SS and POP SS instructions inhibit interrupts (including NMIs), data breakpoints, and single step trap exceptions until the instruction boundary following the next instruction (SDM Vol. 3A; section 6.8.3). (The inhibited data breakpoints are those on memory accessed by the MOV to SS or POP to SS instruction itself.) Note that debug exceptions are not inhibited by the interrupt enable (EFLAGS.IF) system flag (SDM Vol. 3A; section 2.3). If the instruction following the MOV to SS or POP to SS instruction is an instruction like SYSCALL, SYSENTER, INT 3, etc. that transfers control to the operating system at CPL < 3, the debug exception is delivered after the transfer to CPL < 3 is complete. OS kernels may not expect this order of events and may therefore experience unexpected behavior when it occurs.

Race condition in the sclp_ctl_ioctl_sccb function in drivers/s390/char/sclp_ctl.c in the Linux kernel before 4.6 allows local users to obtain sensitive information from kernel memory by changing a certain length value, aka a "double fetch" vulnerability.

Race condition in the handle_to_path function in fs/fhandle.c in the Linux kernel through 3.19.1 allows local users to bypass intended size restrictions and trigger read operations on additional memory locations by changing the handle_bytes value of a file handle during the execution of this function.