Multiple Vendor TCP Initial Sequence Number Statistical Vulnerability

BID:2682

Info

Multiple Vendor TCP Initial Sequence Number Statistical Vulnerability

Bugtraq ID: 2682
Class: Design Error
CVE: CVE-2001-0328
CVE-2001-0288
Remote: Yes
Local: Yes
Published: Mar 14 2001 12:00AM
Updated: Oct 26 2016 05:08AM
Credit: Originally discovered by Tim Newsham <[email protected]>.
Vulnerable: Sun Solaris 7.0
SGI IRIX 6.5.14 m
SGI IRIX 6.5.14 f
SGI IRIX 6.5.14
SGI IRIX 6.5.13 m
SGI IRIX 6.5.13 f
SGI IRIX 6.5.13
SGI IRIX 6.5.12 m
SGI IRIX 6.5.12 f
SGI IRIX 6.5.12
SGI IRIX 6.5.11 m
SGI IRIX 6.5.11 f
SGI IRIX 6.5.11
SGI IRIX 6.5.10 m
SGI IRIX 6.5.10 f
SGI IRIX 6.5.10
SGI IRIX 6.5.9 m
SGI IRIX 6.5.9 f
SGI IRIX 6.5.9
SGI IRIX 6.5.8 m
SGI IRIX 6.5.8 f
SGI IRIX 6.5.8
SGI IRIX 6.5.7 m
SGI IRIX 6.5.7 f
SGI IRIX 6.5.7
SGI IRIX 6.5.6 m
SGI IRIX 6.5.6 f
SGI IRIX 6.5.6
SGI IRIX 6.5.5 m
SGI IRIX 6.5.5 f
SGI IRIX 6.5.5
SGI IRIX 6.5.4 m
SGI IRIX 6.5.4 f
SGI IRIX 6.5.4
SGI IRIX 6.5.3 m
SGI IRIX 6.5.3 f
SGI IRIX 6.5.3
SGI IRIX 6.5.2 m
SGI IRIX 6.5.2 f
SGI IRIX 6.5.2
SGI IRIX 6.5.1
SGI IRIX 6.5
OpenBSD OpenBSD 2.8
Microsoft Windows NT Workstation 4.0 SP6a
Microsoft Windows NT Workstation 4.0 SP6
Microsoft Windows NT Workstation 4.0 SP5
Microsoft Windows NT Workstation 4.0 SP4
Microsoft Windows NT Workstation 4.0 SP3
Microsoft Windows NT Workstation 4.0 SP2
Microsoft Windows NT Workstation 4.0 SP1
Microsoft Windows NT Workstation 4.0
Microsoft Windows NT Terminal Server 4.0 SP6
Microsoft Windows NT Terminal Server 4.0 SP5
Microsoft Windows NT Terminal Server 4.0 SP4
Microsoft Windows NT Terminal Server 4.0 SP3
Microsoft Windows NT Terminal Server 4.0 SP2
Microsoft Windows NT Terminal Server 4.0 SP1
Microsoft Windows NT Terminal Server 4.0
Microsoft Windows NT Server 4.0 SP6a
Microsoft Windows NT Server 4.0 SP6
Microsoft Windows NT Server 4.0 SP5
Microsoft Windows NT Server 4.0 SP4
Microsoft Windows NT Server 4.0 SP3
Microsoft Windows NT Server 4.0 SP2
Microsoft Windows NT Server 4.0 SP1
Microsoft Windows NT Server 4.0
Microsoft Windows NT Enterprise Server 4.0 SP6a
Microsoft Windows NT Enterprise Server 4.0 SP6
Microsoft Windows NT Enterprise Server 4.0 SP5
Microsoft Windows NT Enterprise Server 4.0 SP4
Microsoft Windows NT Enterprise Server 4.0 SP3
Microsoft Windows NT Enterprise Server 4.0 SP2
Microsoft Windows NT Enterprise Server 4.0 SP1
Microsoft Windows NT Enterprise Server 4.0
Microsoft Windows NT 4.0 SP6
+ Microsoft Windows NT Enterprise Server 4.0 SP6
 + Microsoft Windows NT Enterprise Server 4.0 SP6
 + Microsoft Windows NT Server 4.0 SP6
 + Microsoft Windows NT Server 4.0 SP6
 + Microsoft Windows NT Terminal Server 4.0 SP6
 + Microsoft Windows NT Terminal Server 4.0 SP6
 + Microsoft Windows NT Workstation 4.0 SP6
 + Microsoft Windows NT Workstation 4.0 SP6
 Microsoft Windows NT 4.0 SP5
Microsoft Windows NT 4.0 SP4
+ Microsoft Windows NT Enterprise Server 4.0 SP4
 + Microsoft Windows NT Enterprise Server 4.0 SP4
 + Microsoft Windows NT Server 4.0 SP4
 + Microsoft Windows NT Server 4.0 SP4
 + Microsoft Windows NT Terminal Server 4.0 SP4
 + Microsoft Windows NT Terminal Server 4.0 SP4
 + Microsoft Windows NT Workstation 4.0 SP4
 + Microsoft Windows NT Workstation 4.0 SP4
 Microsoft Windows NT 4.0 SP3
Microsoft Windows NT 4.0 SP2
Microsoft Windows NT 4.0 SP1
Microsoft Windows NT 4.0
+ Microsoft Windows NT Enterprise Server 4.0
 + Microsoft Windows NT Enterprise Server 4.0
 + Microsoft Windows NT Server 4.0
 + Microsoft Windows NT Server 4.0
 + Microsoft Windows NT Terminal Server 4.0
 + Microsoft Windows NT Terminal Server 4.0
 + Microsoft Windows NT Workstation 4.0
 + Microsoft Windows NT Workstation 4.0
 Microsoft Windows 98SE
Microsoft Windows 98
Microsoft Windows 95
Linux kernel 2.1 .x
Linux kernel 2.0 .x
IBM AIX 4.3
HP HP-UX 11.11
HP HP-UX 11.0 4
HP HP-UX 11.0
HP HP-UX 10.20
HP HP-UX 10.0
FreeBSD FreeBSD 4.2 -STABLEpre050201
FreeBSD FreeBSD 3.5 -STABLEpre050201
Cisco IOS 12.1YD
Cisco IOS 12.1YC
Cisco IOS 12.1YB
Cisco IOS 12.1YA
Cisco IOS 12.1XZ
Cisco IOS 12.1XY
Cisco IOS 12.1XX
Cisco IOS 12.1XW
Cisco IOS 12.1XV
Cisco IOS 12.1XU
Cisco IOS 12.1XT
Cisco IOS 12.1XS
Cisco IOS 12.1XR
Cisco IOS 12.1XQ
Cisco IOS 12.1XP
Cisco IOS 12.1XM
Cisco IOS 12.1XL
Cisco IOS 12.1XK
Cisco IOS 12.1XJ
Cisco IOS 12.1XI
Cisco IOS 12.1XH
Cisco IOS 12.1XG
Cisco IOS 12.1XF
Cisco IOS 12.1XE
Cisco IOS 12.1XD
Cisco IOS 12.1XC
Cisco IOS 12.1XB
Cisco IOS 12.1XA
Cisco IOS 12.1T
Cisco IOS 12.1EX
Cisco IOS 12.1EC
Cisco IOS 12.1E
Cisco IOS 12.1DC
Cisco IOS 12.1DB
Cisco IOS 12.1DA
Cisco IOS 12.1CX
Cisco IOS 12.1AA
Cisco IOS 12.1
Cisco IOS 12.0XV
Cisco IOS 12.0XU
Cisco IOS 12.0XS
Cisco IOS 12.0XR
Cisco IOS 12.0XQ
Cisco IOS 12.0XP
Cisco IOS 12.0XN
Cisco IOS 12.0XM
Cisco IOS 12.0XL
Cisco IOS 12.0XK
Cisco IOS 12.0XJ
Cisco IOS 12.0XI
Cisco IOS 12.0XH
Cisco IOS 12.0XG
Cisco IOS 12.0XF
Cisco IOS 12.0XE
Cisco IOS 12.0XD
Cisco IOS 12.0XC
Cisco IOS 12.0XB
Cisco IOS 12.0XA
Cisco IOS 12.0WT
Cisco IOS 12.0W5
Cisco IOS 12.0T
Cisco IOS 12.0SX
Cisco IOS 12.0ST
Cisco IOS 12.0SL
Cisco IOS 12.0SC
Cisco IOS 12.0S
Cisco IOS 12.0DC
Cisco IOS 12.0DB
Cisco IOS 12.0DA
Cisco IOS 12.0
Cisco IOS 11.3WA4
Cisco IOS 11.3T
Cisco IOS 11.3NA
Cisco IOS 11.3MA
Cisco IOS 11.3HA
Cisco IOS 11.3DB
Cisco IOS 11.3DA
Cisco IOS 11.3AA
Cisco IOS 11.3(2)XA
Cisco IOS 11.3
Cisco IOS 11.2WA3
Cisco IOS 11.2SA
Cisco IOS 11.2P
Cisco IOS 11.2GS
Cisco IOS 11.2F
Cisco IOS 11.2BC
Cisco IOS 11.2(9)XA
Cisco IOS 11.2(4)XA
Cisco IOS 11.2
Cisco IOS 11.1IA
Cisco IOS 11.1CT
Cisco IOS 11.1CC
Cisco IOS 11.1CA
Cisco IOS 11.1AA
Cisco IOS 11.1
Cisco IOS 11.0
BSDI BSD/OS 4.0
BSDI BSD/OS 3.0
Apple Mac OS X 10.0.2
Apple Mac OS X 10.0.1
Apple Mac OS X 10.0
Apple Mac OS 9 9.1
Apple Mac OS 9 9.0.4
Apple Mac OS 9 9.0
Apple Mac OS 8 8.6
Apple Mac OS 8 8.5
Apple Mac OS 8 8.1
Apple Mac OS 8 8.0
Apple Mac OS 7 7.6.1
Apple Mac OS 7 7.6
Apple Mac OS 7 7.5.3
Apple Mac OS 7 7.5.2
Apple Mac OS 7 7.5.1
Apple Mac OS 7 7.1.2
Apple Mac OS 7 7.1
Apple Mac OS 7 7.0.1
Apple Mac OS 7 7.0
ABB RTU500 Series 11.3
Not Vulnerable: Linux kernel 2.2 .x
+ Redhat Linux 6.2 sparc
 + Redhat Linux 6.2 i386
 + Redhat Linux 6.2 alpha
 ABB RTU500 Series 11.4.1

Discussion

Multiple Vendor TCP Initial Sequence Number Statistical Vulnerability

Over the past several years, a variety of attacks against TCP initial sequence number (ISN) generation have been discussed.

A vulnerability exists in some TCP/IP stack implementations that use random increments for initial sequence numbers. Such implementations are vulnerable to statistical attack, which could allow an attacker to predict, within a reasonable range, sequence numbers of future and existing connections.

By predicting a sequence number, several attacks could be performed; an attacker could disrupt or hijack existing connections, or spoof future connections.

Exploit / POC

Multiple Vendor TCP Initial Sequence Number Statistical Vulnerability

Currently the SecurityFocus staff are not aware of any exploits for this issue. If you feel we are in error or are aware of more recent information, please mail us at: [email protected] &lt;mailto:[email protected]&gt;.

Solution / Fix

Multiple Vendor TCP Initial Sequence Number Statistical Vulnerability

Solution:
Under Solaris 7, it has been suggested that the feasibility of this attack is eliminated by setting "tcp_strong_iss=2".

SGI has suggests the tcpiss_md5 kernel parameter may eliminate this vulnerability. Details are available in the SGI advisory 20020303-01-A listed as a reference. This parameter is disabled by default.

SGI has released a second advisory for this issue which contains fixes for the IRIX operating system. Users are advised to upgrade their systems as soon as possible.

Users of HP-UX 11.0 may install patch PHNE_22397 to enable HP randomization of initial sequence numbers.

Users of HP-UX 11.0, 11.04 and 11.11 may enable RFC 1948 compliant randomization through patches PHNE_26771, PHNE_26101, or PHNE_25644 respectively. Once patched, the following shell command must be executed by root:

ndd -set /dev/tcp tcp_isn_passphrase <secret passphrase>

Where <secret passphrase> is any length character string. Only the first 32 characters will be retained. If the passphrase is changed the system should be rebooted.

Several vendors have released kernel patches and upgrades which address this issue:


Cisco IOS 12.0SC
  • Cisco IOS 12.0(15)SC1


Cisco IOS 12.0XA
  • Cisco IOS 12.1(7)


Cisco IOS 12.1XQ
  • Cisco IOS 12.1(3)XQ1


Cisco IOS 12.1XJ
  • Cisco IOS 12.1(5)YB


Cisco IOS 12.1XI
  • Cisco IOS 12.1(3)XI6


Cisco IOS 12.1XS
  • Cisco IOS 12.1(5c)EX


Cisco IOS 12.0XB
  • Cisco IOS 12.1(7)


Cisco IOS 12.1XV
  • Cisco IOS 12.1(5)XV1


Cisco IOS 11.0
  • Cisco IOS 11.0(22a)


Cisco IOS 12.0XG
  • Cisco IOS 12.1(7)


Cisco IOS 12.1YD
  • Cisco IOS 12.1(5)YD


Cisco IOS 12.0XS
  • Cisco IOS 12.1(5c)E8


Cisco IOS 12.1XX
  • Cisco IOS 12.1(5)XX3


Cisco IOS 11.3
  • Cisco IOS 11.3(11b)


Cisco IOS 12.1XM
  • Cisco IOS 12.0(5)XM1


Cisco IOS 12.0XK
  • Cisco IOS 12.0(7)XK4


Cisco IOS 12.1XY
  • Cisco IOS 12.1(5)XY4


Cisco IOS 12.1XL
  • Cisco IOS 12.1(3)XL1


Cisco IOS 12.1XT
  • Cisco IOS 12.1(3)XT1


Cisco IOS 11.1CC
  • Cisco IOS 11.1(36)CC1


Cisco IOS 11.1CA
  • Cisco IOS 11.1(36)CA1


Cisco IOS 11.2P
  • Cisco IOS 11.2(25a)P


Cisco IOS 12.0XH
  • Cisco IOS 12.0(4)XH5


Cisco IOS 12.0DC
  • Cisco IOS 12.1(4)DC2


Cisco IOS 12.0T
  • Cisco IOS 12.1(7)


Cisco IOS 11.3NA
  • Cisco IOS 12.1(7)


Cisco IOS 11.2
  • Cisco IOS 11.2(25a)


Cisco IOS 11.3AA
  • Cisco IOS 11.3(11a)AA


Cisco IOS 12.1YA
  • Cisco IOS 12.1(5)YA1


Cisco IOS 12.1YB
  • Cisco IOS 12.1(5)YB


Cisco IOS 12.1XG
  • Cisco IOS 12.1(3)XG3


Cisco IOS 11.1
  • Cisco IOS 11.1(24a)


Cisco IOS 11.2GS
  • Cisco IOS 12.0(15)S1


Cisco IOS 11.3(2)XA
  • Cisco IOS 11.3(11b)T1


FreeBSD FreeBSD 3.5 -STABLEpre050201

SGI IRIX 6.5.14 f

SGI IRIX 6.5.14 m

References

Multiple Vendor TCP Initial Sequence Number Statistical Vulnerability

References:

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