CVE Vulnerabilities


Improper Restriction of Operations within the Bounds of a Memory Buffer

Published: Sep 23, 2019 | Modified: Nov 07, 2023
CVSS 3.x
CVSS 2.x
5.8 LOW

Hunspell 1.7.0 has an invalid read operation in SuggestMgr::leftcommonsubstring in suggestmgr.cxx.


The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer.

Affected Software

Name Vendor Start Version End Version
Hunspell Hunspell_project 1.7.0 (including) 1.7.0 (including)
Red Hat Enterprise Linux 7 RedHat hunspell-0:1.3.2-16.el7 *
Calibre Ubuntu bionic *
Calibre Ubuntu disco *
Calibre Ubuntu eoan *
Calibre Ubuntu groovy *
Calibre Ubuntu hirsute *
Calibre Ubuntu impish *
Calibre Ubuntu kinetic *
Calibre Ubuntu lunar *
Calibre Ubuntu trusty *
Calibre Ubuntu xenial *
Chromium Ubuntu trusty *
Enchant Ubuntu bionic *
Enchant Ubuntu disco *
Enchant Ubuntu eoan *
Enchant Ubuntu groovy *
Enchant Ubuntu trusty *
Enchant Ubuntu xenial *
Firefox Ubuntu disco *
Firefox Ubuntu trusty *
Focuswriter Ubuntu bionic *
Focuswriter Ubuntu disco *
Focuswriter Ubuntu eoan *
Focuswriter Ubuntu groovy *
Focuswriter Ubuntu hirsute *
Focuswriter Ubuntu impish *
Focuswriter Ubuntu kinetic *
Focuswriter Ubuntu lunar *
Focuswriter Ubuntu trusty *
Focuswriter Ubuntu xenial *
Hunspell Ubuntu bionic *
Hunspell Ubuntu disco *
Hunspell Ubuntu eoan *
Hunspell Ubuntu groovy *
Hunspell Ubuntu hirsute *
Hunspell Ubuntu impish *
Hunspell Ubuntu kinetic *
Hunspell Ubuntu lunar *
Hunspell Ubuntu trusty *
Hunspell Ubuntu xenial *
Postbooks Ubuntu bionic *
Postbooks Ubuntu disco *
Postbooks Ubuntu eoan *
Postbooks Ubuntu trusty *
Postbooks Ubuntu xenial *
Qtwebengine-opensource-src Ubuntu bionic *
Qtwebengine-opensource-src Ubuntu disco *
Qtwebengine-opensource-src Ubuntu eoan *
Qtwebengine-opensource-src Ubuntu groovy *
Qtwebengine-opensource-src Ubuntu hirsute *
Qtwebengine-opensource-src Ubuntu impish *
Qtwebengine-opensource-src Ubuntu kinetic *
Qtwebengine-opensource-src Ubuntu lunar *
Qtwebengine-opensource-src Ubuntu trusty *
Texmaker Ubuntu bionic *
Texmaker Ubuntu disco *
Texmaker Ubuntu eoan *
Texmaker Ubuntu groovy *
Texmaker Ubuntu hirsute *
Texmaker Ubuntu impish *
Texmaker Ubuntu kinetic *
Texmaker Ubuntu lunar *
Texmaker Ubuntu trusty *
Texmaker Ubuntu xenial *
Thunderbird Ubuntu disco *
Thunderbird Ubuntu trusty *

Extended Description

Certain languages allow direct addressing of memory locations and do not automatically ensure that these locations are valid for the memory buffer that is being referenced. This can cause read or write operations to be performed on memory locations that may be associated with other variables, data structures, or internal program data. As a result, an attacker may be able to execute arbitrary code, alter the intended control flow, read sensitive information, or cause the system to crash.

Potential Mitigations

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

  • For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer.

  • Be wary that a language’s interface to native code may still be subject to overflows, even if the language itself is theoretically safe.

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

  • Examples include the Safe C String Library (SafeStr) by Messier and Viega [REF-57], and the Strsafe.h library from Microsoft [REF-56]. These libraries provide safer versions of overflow-prone string-handling functions.

  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking.

  • D3-SFCV (Stack Frame Canary Validation) from D3FEND [REF-1334] discusses canary-based detection in detail.

  • Consider adhering to the following rules when allocating and managing an application’s memory:

  • Run or compile the software using features or extensions that randomly arrange the positions of a program’s executable and libraries in memory. Because this makes the addresses unpredictable, it can prevent an attacker from reliably jumping to exploitable code.

  • Examples include Address Space Layout Randomization (ASLR) [REF-58] [REF-60] and Position-Independent Executables (PIE) [REF-64]. Imported modules may be similarly realigned if their default memory addresses conflict with other modules, in a process known as “rebasing” (for Windows) and “prelinking” (for Linux) [REF-1332] using randomly generated addresses. ASLR for libraries cannot be used in conjunction with prelink since it would require relocating the libraries at run-time, defeating the whole purpose of prelinking.

  • For more information on these techniques see D3-SAOR (Segment Address Offset Randomization) from D3FEND [REF-1335].

  • Use a CPU and operating system that offers Data Execution Protection (using hardware NX or XD bits) or the equivalent techniques that simulate this feature in software, such as PaX [REF-60] [REF-61]. These techniques ensure that any instruction executed is exclusively at a memory address that is part of the code segment.

  • For more information on these techniques see D3-PSEP (Process Segment Execution Prevention) from D3FEND [REF-1336].