A heap-based buffer overflow exists in GNU Bash before 4.3 when wide characters, not supported by the current locale set in the LC_CTYPE environment variable, are printed through the echo built-in function. A local attacker, who can provide data to print through the "echo -e" built-in function, may use this flaw to crash a script or execute code with the privileges of the bash process. This occurs because ansicstr() in lib/sh/strtrans.c mishandles u32cconv().
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
| Link | Tags |
|---|---|
| https://bugzilla.redhat.com/show_bug.cgi?id=1721071 | issue tracking third party advisory |
| http://git.savannah.gnu.org/cgit/bash.git/commit/?h=devel&id=863d31ae775d56b785dc5b0105b6d251515d81d5 | mailing list third party advisory patch |
| http://www.securityfocus.com/bid/108824 | vdb entry |
| https://support.f5.com/csp/article/K05122252 | |
| https://support.f5.com/csp/article/K05122252?utm_source=f5support&%3Butm_medium=RSS | |
| https://usn.ubuntu.com/4180-1/ | vendor advisory |