Arch Linux Security Advisory ASA-201707-20

Severity: Medium
Date : 2017-07-18
CVE-ID : CVE-2017-7186 CVE-2017-7244 CVE-2017-7245 CVE-2017-7246
Package : pcre
Type : multiple issues
Remote : Yes
Link : https://security.archlinux.org/AVG-222

Summary

The package pcre before version 8.41-1 is vulnerable to multiple issues
including denial of service and arbitrary code execution.

Resolution

Upgrade to 8.41-1.

pacman -Syu “pcre>=8.41-1”

The problems have been fixed upstream in version 8.41.

Workaround

None.

Description

• CVE-2017-7186 (denial of service)

libpcre1 in PCRE 8.40 and libpcre2 in PCRE2 10.23 allow remote
attackers to cause a denial of service (segmentation violation for read
access, and application crash) by triggering an invalid Unicode
property lookup.

• CVE-2017-7244 (denial of service)

A stack-based read buffer overflow has been found in libpcre <= 8.40,
in the pcretest utility. It can lead to denial of service via a crafted
expression passed to the pcretest command.

• CVE-2017-7245 (arbitrary code execution)

A stack-based write buffer overflow has been found in libpcre <= 8.40,
in the pcretest utility. It can lead to arbitrary code execution via a
crafted expression passed to the pcretest command.

• CVE-2017-7246 (arbitrary code execution)

A stack-based write buffer overflow has been found in libpcre <= 8.40,
in the pcretest utility. It can lead to arbitrary code execution via a
crafted expression passed to the pcretest command.

Impact

An attacker can execute arbitrary code on the affected host by tricking
a user into passing a crafted expression to the pcretest command. A
remote attacker can cause a denial of service against an application
using libpcre via a crafted expression.

References

https://vcs.pcre.org/pcre/code/trunk/pcre_ucd.c?r1=1490&r2=1688&sortby=date
https://blogs.gentoo.org/ago/2017/03/20/libpcre-two-stack-based-buffer-overflow-write-in-pcre32_copy_substring-pcre_get-c/
https://blogs.gentoo.org/ago/2017/03/20/libpcre-invalid-memory-read-in-_pcre32_xclass-pcre_xclass-c/
https://bugs.exim.org/show_bug.cgi?id=2052
https://blogs.gentoo.org/ago/2017/03/14/libpcre-invalid-memory-read-in-match-pcre_exec-c/
https://vcs.pcre.org/pcre2/code/trunk/src/pcre2_internal.h?r1=600&r2=670&sortby=date
https://vcs.pcre.org/pcre2/code/trunk/src/pcre2_ucd.c?r1=316&r2=670&sortby=date
https://security.archlinux.org/CVE-2017-7186
https://security.archlinux.org/CVE-2017-7244
https://security.archlinux.org/CVE-2017-7245
https://security.archlinux.org/CVE-2017-7246