CVE Vulnerabilities

CVE-2015-1606

Use After Free

Published: Nov 20, 2019 | Modified: Nov 22, 2019
CVSS 3.x
5.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CVSS 2.x
4.3 MEDIUM
AV:N/AC:M/Au:N/C:N/I:N/A:P
RedHat/V2
1.2 LOW
AV:L/AC:H/Au:N/C:P/I:N/A:N
RedHat/V3
Ubuntu

The keyring DB in GnuPG before 2.1.2 does not properly handle invalid packets, which allows remote attackers to cause a denial of service (invalid read and use-after-free) via a crafted keyring file.

Weakness

Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code.

Affected Software

Name Vendor Start Version End Version
Gnupg Gnupg * *
Gnupg Ubuntu lucid *
Gnupg Ubuntu precise *
Gnupg Ubuntu trusty *
Gnupg Ubuntu trusty/esm *
Gnupg Ubuntu upstream *
Gnupg Ubuntu utopic *
Gnupg2 Ubuntu devel *
Gnupg2 Ubuntu lucid *
Gnupg2 Ubuntu precise *
Gnupg2 Ubuntu trusty *
Gnupg2 Ubuntu upstream *
Gnupg2 Ubuntu utopic *

Extended Description

The use of previously-freed memory can have any number of adverse consequences, ranging from the corruption of valid data to the execution of arbitrary code, depending on the instantiation and timing of the flaw. The simplest way data corruption may occur involves the system’s reuse of the freed memory. Use-after-free errors have two common and sometimes overlapping causes:

In this scenario, the memory in question is allocated to another pointer validly at some point after it has been freed. The original pointer to the freed memory is used again and points to somewhere within the new allocation. As the data is changed, it corrupts the validly used memory; this induces undefined behavior in the process. If the newly allocated data chances to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.

Potential Mitigations

References