7.1
CWE
287
Advisory Published
Updated

CVE-2005-1020

First published: Sat Apr 09 2005(Updated: )

Secure Shell (SSH) 2 in Cisco IOS 12.0 through 12.3 allows remote attackers to cause a denial of service (device reload) (1) via a username that contains a domain name when using a TACACS+ server to authenticate, (2) when a new SSH session is in the login phase and a currently logged in user issues a send command, or (3) when IOS is logging messages and an SSH session is terminated while the server is sending data.

Credit: cve@mitre.org

Affected SoftwareAffected VersionHow to fix
Puppet Cisco IOS=12.1xg
Puppet Cisco IOS=12.0xc
Puppet Cisco IOS=12.3xr
Puppet Cisco IOS=12.0xk
Puppet Cisco IOS=12.0\(27\)s
Puppet Cisco IOS=12.0xr
Puppet Cisco IOS=12.1xm
Puppet Cisco IOS=12.1xi
Puppet Cisco IOS=12.2\(1\)xs
Puppet Cisco IOS=12.2\(1\)xd1
Puppet Cisco IOS=12.1\(19\)e1
Puppet Cisco IOS=12.3bc
Puppet Cisco IOS=12.0st
Puppet Cisco IOS=12.2xr
Puppet Cisco IOS=12.3\(4\)xd1
Puppet Cisco IOS=12.1e
Puppet Cisco IOS=12.1xc
Puppet Cisco IOS=12.3ya
Puppet Cisco IOS=12.1xp
Puppet Cisco IOS=12.2cz
Puppet Cisco IOS=12.2\(1\)xq
Puppet Cisco IOS=12.1\(11\)e
Puppet Cisco IOS=12.3yl
Puppet Cisco IOS=12.1ya
Puppet Cisco IOS=12.1yd
Puppet Cisco IOS=12.0dc
Puppet Cisco IOS=12.2\(1\)xd3
Puppet Cisco IOS=12.2zn
Puppet Cisco IOS=12.2\(18\)sw
Puppet Cisco IOS=12.0xq
Puppet Cisco IOS=12.1xs
Puppet Cisco IOS=12.2xe
Puppet Cisco IOS=12.0xe
Puppet Cisco IOS=12.3xs
Puppet Cisco IOS=12.2ja
Puppet Cisco IOS=12.2sx
Puppet Cisco IOS=12.1\(13\)e9
Puppet Cisco IOS=12.3\(5a\)
Puppet Cisco IOS=12.3xg
Puppet Cisco IOS=12.2\(14\)sy
Puppet Cisco IOS=12.1\(11b\)e14
Puppet Cisco IOS=12.2zp
Puppet Cisco IOS=12.0sv
Puppet Cisco IOS=12.3bw
Puppet Cisco IOS=12.2\(20\)s1
Puppet Cisco IOS=12.2\(21a\)
Puppet Cisco IOS=12.1xy
Puppet Cisco IOS=12.2\(1\)xs1
Puppet Cisco IOS=12.3xd
Puppet Cisco IOS=12.3xm
Puppet Cisco IOS=12.2bz
Puppet Cisco IOS=12.2zi
Puppet Cisco IOS=12.1\(20\)e1
Puppet Cisco IOS=12.2\(4\)ja1
Puppet Cisco IOS=12.2ys
Puppet Cisco IOS=12.0xd
Puppet Cisco IOS=12.3xw
Puppet Cisco IOS=12.2\(2\)xk
Puppet Cisco IOS=12.2xz
Puppet Cisco IOS=12.2xj
Puppet Cisco IOS=12.2su
Puppet Cisco IOS=12.1xz
Puppet Cisco IOS=12.2xh
Puppet Cisco IOS=12.2xg
Puppet Cisco IOS=12.2ew
Puppet Cisco IOS=12.0xj
Puppet Cisco IOS=12.2b
Puppet Cisco IOS=12.1\(20\)ea1
Puppet Cisco IOS=12.1t
Puppet Cisco IOS=12.2\(2\)xb4
Puppet Cisco IOS=12.1eo
Puppet Cisco IOS=12.3xi
Puppet Cisco IOS=12.2\(14.5\)t
Puppet Cisco IOS=12.1xr
Puppet Cisco IOS=12.3\(4\)t2
Puppet Cisco IOS=12.2yn
Puppet Cisco IOS=12.3\(5a\)b
Puppet Cisco IOS=12.1az
Puppet Cisco IOS=12.2sxa
Puppet Cisco IOS=12.2\(14\)za2
Puppet Cisco IOS=12.1db
Puppet Cisco IOS=12.2\(2\)xj1
Puppet Cisco IOS=12.3yj
Puppet Cisco IOS=12.1\(20\)ec
Puppet Cisco IOS=12.2xb
Puppet Cisco IOS=12.2yf
Puppet Cisco IOS=12.1\(20\)ec1
Puppet Cisco IOS=12.1xe
Puppet Cisco IOS=12.2\(2\)xu
Puppet Cisco IOS=12.2xl
Puppet Cisco IOS=12.2ym
Puppet Cisco IOS=12.3xt
Puppet Cisco IOS=12.2yw
Puppet Cisco IOS=12.2yd
Puppet Cisco IOS=12.2\(1\)xa
Puppet Cisco IOS=12.3xj
Puppet Cisco IOS=12.0xl
Puppet Cisco IOS=12.2\(2\)t4
Puppet Cisco IOS=12.0xs
Puppet Cisco IOS=12.3t
Puppet Cisco IOS=12.2yb
Puppet Cisco IOS=12.3
Puppet Cisco IOS=12.3\(5\)
Puppet Cisco IOS=12.2mb
Puppet Cisco IOS=12.3\(4\)t3
Puppet Cisco IOS=12.2dd
Puppet Cisco IOS=12.1eu
Puppet Cisco IOS=12.2\(2\)xh3
Puppet Cisco IOS=12.1xb
Puppet Cisco IOS=12.0\(24.2\)s
Puppet Cisco IOS=12.2zh
Puppet Cisco IOS=12.2da
Puppet Cisco IOS=12.0\(24\)s1
Puppet Cisco IOS=12.1yf
Puppet Cisco IOS=12.2mx
Puppet Cisco IOS=12.2yv
Puppet Cisco IOS=12.1xl
Puppet Cisco IOS=12.1ax
Puppet Cisco IOS=12.2\(1\)xe2
Puppet Cisco IOS=12.2sxb
Puppet Cisco IOS=12.2yo
Puppet Cisco IOS=12.2\(15\)zn
Puppet Cisco IOS=12.1\(20\)e2
Puppet Cisco IOS=12.3\(2\)t3
Puppet Cisco IOS=12.2xw
Puppet Cisco IOS=12.1ev
Puppet Cisco IOS=12.2t
Puppet Cisco IOS=12.2zc
Puppet Cisco IOS=12.0xb
Puppet Cisco IOS=12.1xk
Puppet Cisco IOS=12.2\(1\)xd4
Puppet Cisco IOS=12.2sv
Puppet Cisco IOS=12.3xz
Puppet Cisco IOS=12.2yt
Puppet Cisco IOS=12.2\(2\)xh2
Puppet Cisco IOS=12.2zk
Puppet Cisco IOS=12.0xh
Puppet Cisco IOS=12.0t
Puppet Cisco IOS=12.1xw
Puppet Cisco IOS=12.2yl
Puppet Cisco IOS=12.2za
Puppet Cisco IOS=12.2xn
Puppet Cisco IOS=12.2ye
Puppet Cisco IOS=12.1yb
Puppet Cisco IOS=12.0\(27\)sv
Puppet Cisco IOS=12.0xu
Puppet Cisco IOS=12.3j
Puppet Cisco IOS=12.2\(2\)xh
Puppet Cisco IOS=12.3yd
Puppet Cisco IOS=12.2\(18\)ewa
Puppet Cisco IOS=12.1eb
Puppet Cisco IOS=12.2zb
Puppet Cisco IOS=12.2yg
Puppet Cisco IOS=12.1dc
Puppet Cisco IOS=12.2xu
Puppet Cisco IOS=12.1ex
Puppet Cisco IOS=12.2\(2\)xi
Puppet Cisco IOS=12.1yi
Puppet Cisco IOS=12.3xf
Puppet Cisco IOS=12.3xl
Puppet Cisco IOS=12.2yr
Puppet Cisco IOS=12.2se
Puppet Cisco IOS=12.1
Puppet Cisco IOS=12.1\(20\)ew
Puppet Cisco IOS=12.0sl
Puppet Cisco IOS=12.1yh
Puppet Cisco IOS=12.3\(4\)t
Puppet Cisco IOS=12.0db
Puppet Cisco IOS=12.3yf
Puppet Cisco IOS=12.2\(18\)se
Puppet Cisco IOS=12.2zq
Puppet Cisco IOS=12.0sz
Puppet Cisco IOS=12.1ec
Puppet Cisco IOS=12.2zo
Puppet Cisco IOS=12.2\(2\)xb3
Puppet Cisco IOS=12.2\(11\)ja1
Puppet Cisco IOS=12.1cx
Puppet Cisco IOS=12.0w5
Puppet Cisco IOS=12.2\(11\)ja
Puppet Cisco IOS=12.2xm
Puppet Cisco IOS=12.2\(14\)sy1
Puppet Cisco IOS=12.2sy
Puppet Cisco IOS=12.2\(2\)xa5
Puppet Cisco IOS=12.2xk
Puppet Cisco IOS=12.1xh
Puppet Cisco IOS=12.0\(23\)s5
Puppet Cisco IOS=12.3xb
Puppet Cisco IOS=12.3\(6\)
Puppet Cisco IOS=12.2\(20\)ew
Puppet Cisco IOS=12.2zj
Puppet Cisco IOS=12.2x
Puppet Cisco IOS=12.0xa
Puppet Cisco IOS=12.2\(2\)xi1
Puppet Cisco IOS=12.2\(1\)xh
Puppet Cisco IOS=12.1xu
Puppet Cisco IOS=12.0sc
Puppet Cisco IOS=12.0sy
Puppet Cisco IOS=12.2jk
Puppet Cisco IOS=12.3yg
Puppet Cisco IOS=12.1xj
Puppet Cisco IOS=12.3xu
Puppet Cisco IOS=12.2zd
Puppet Cisco IOS=12.3xy
Puppet Cisco IOS=12.1\(20\)e
Puppet Cisco IOS=12.2cy
Puppet Cisco IOS=12.3xc
Puppet Cisco IOS=12.3\(4\)xd
Puppet Cisco IOS=12.1aa
Puppet Cisco IOS=12.0xn
Puppet Cisco IOS=12.2xc
Puppet Cisco IOS=12.3\(4\)t1
Puppet Cisco IOS=12.2ewa
Puppet Cisco IOS=12.2\(2\)xt
Puppet Cisco IOS=12.2\(2\)xj
Puppet Cisco IOS=12.3xv
Puppet Cisco IOS=12.2\(16\)b
Puppet Cisco IOS=12.2bc
Puppet Cisco IOS=12.3xe
Puppet Cisco IOS=12.0da
Puppet Cisco IOS=12.1xx
Puppet Cisco IOS=12.0\(24\)s4
Puppet Cisco IOS=12.2\(1\)xd
Puppet Cisco IOS=12.0sp
Puppet Cisco IOS=12.2yc
Puppet Cisco IOS=12.2ze
Puppet Cisco IOS=12.2\(2\)xk2
Puppet Cisco IOS=12.3ja
Puppet Cisco IOS=12.2\(11\)t
Puppet Cisco IOS=12.1\(11b\)e12
Puppet Cisco IOS=12.2xs
Puppet Cisco IOS=12.0\(26\)s1
Puppet Cisco IOS=12.2yp
Puppet Cisco IOS=12.2bw
Puppet Cisco IOS=12.2\(2\)xt3
Puppet Cisco IOS=12.2yy
Puppet Cisco IOS=12.2sz
Puppet Cisco IOS=12.2xi
Puppet Cisco IOS=12.0\(27\)sv1
Puppet Cisco IOS=12.1\(20\)ew1
Puppet Cisco IOS=12.3\(5b\)
Puppet Cisco IOS=12.0wc
Puppet Cisco IOS=12.2\(18\)s
Puppet Cisco IOS=12.1ey
Puppet Cisco IOS=12.2yu
Puppet Cisco IOS=12.0wx
Puppet Cisco IOS=12.2\(18\)sv
Puppet Cisco IOS=12.2\(2\)xf
Puppet Cisco IOS=12.2\(15.1\)s
Puppet Cisco IOS=12.2\(2\)xu2
Puppet Cisco IOS=12.0xm
Puppet Cisco IOS=12.0\(24\)s5
Puppet Cisco IOS=12.1xd
Puppet Cisco IOS=12.2dx
Puppet Cisco IOS=12.2\(2\)xn
Puppet Cisco IOS=12.2xd
Puppet Cisco IOS=12.2bx
Puppet Cisco IOS=12.2\(23\)
Puppet Cisco IOS=12.3xq
Puppet Cisco IOS=12.2\(4\)ja
Puppet Cisco IOS=12.2cx
Puppet Cisco IOS=12.2zl
Puppet Cisco IOS=12.2\(2\)xi2
Puppet Cisco IOS=12.2yq
Puppet Cisco IOS=12.3\(2\)xc2
Puppet Cisco IOS=12.3xh
Puppet Cisco IOS=12.2\(2\)xa
Puppet Cisco IOS=12.1xq
Puppet Cisco IOS=12.2\(12h\)
Puppet Cisco IOS=12.0s
Puppet Cisco IOS=12.2\(1\)xe3
Puppet Cisco IOS=12.2xf
Puppet Cisco IOS=12.0xt
Puppet Cisco IOS=12.0wt
Puppet Cisco IOS=12.1ay
Puppet Cisco IOS=12.2xq
Puppet Cisco IOS=12.3\(2\)xc1
Puppet Cisco IOS=12.2\(18\)ew
Puppet Cisco IOS=12.2\(1\)xe
Puppet Cisco IOS=12.1ea
Puppet Cisco IOS=12.2zf
Puppet Cisco IOS=12.3b
Puppet Cisco IOS=12.1xf
Puppet Cisco IOS=12.3yh
Puppet Cisco IOS=12.2ya
Puppet Cisco IOS=12.1ew
Puppet Cisco IOS=12.2\(14.5\)
Puppet Cisco IOS=12.1da
Puppet Cisco IOS=12.0xw
Puppet Cisco IOS=12.2
Puppet Cisco IOS=12.1xa
Puppet Cisco IOS=12.0xg
Puppet Cisco IOS=12.2\(2\)xb
Puppet Cisco IOS=12.2zg
Puppet Cisco IOS=12.3xx
Puppet Cisco IOS=12.2\(8\)ja
Puppet Cisco IOS=12.0
Puppet Cisco IOS=12.0\(23\)s4
Puppet Cisco IOS=12.1yc
Puppet Cisco IOS=12.2sw
Puppet Cisco IOS=12.0xp
Puppet Cisco IOS=12.3xa
Puppet Cisco IOS=12.2\(20\)s
Puppet Cisco IOS=12.0xv
Puppet Cisco IOS=12.2\(14\)za
Puppet Cisco IOS=12.2yk
Puppet Cisco IOS=12.2sxd
Puppet Cisco IOS=12.3yc
Puppet Cisco IOS=12.2yz
Puppet Cisco IOS=12.2\(16.1\)b
Puppet Cisco IOS=12.2xa
Puppet Cisco IOS=12.1xt
Puppet Cisco IOS=12.2\(2\)xa1
Puppet Cisco IOS=12.2\(12g\)
Puppet Cisco IOS=12.1m
Puppet Cisco IOS=12.0sx
Puppet Cisco IOS=12.2zm
Puppet Cisco IOS=12.2\(2\)xg
Puppet Cisco IOS=12.3ye
Puppet Cisco IOS=12.0xf
Puppet Cisco IOS=12.0xi
Puppet Cisco IOS=12.1ye
Puppet Cisco IOS=12.1\(11b\)e
Puppet Cisco IOS=12.3xk
Puppet Cisco IOS=12.1xv
Puppet Cisco IOS=12.2yj
Puppet Cisco IOS=12.2\(21\)
Puppet Cisco IOS=12.2\(14\)sz
Puppet Cisco IOS=12.2mc
Puppet Cisco IOS=12.1yj
Puppet Cisco IOS=12.3xn
Puppet Cisco IOS=12.2yx
Puppet Cisco IOS=12.1\(20\)eo
Puppet Cisco IOS=12.2\(17a\)sxa
Puppet Cisco IOS=12.2by
Puppet Cisco IOS=12.2yh
Puppet Cisco IOS=12.2s
Puppet Cisco IOS=12.2xt

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Frequently Asked Questions

  • What is the severity of CVE-2005-1020?

    CVE-2005-1020 is classified as a high severity vulnerability that allows attackers to cause a denial of service on affected Cisco IOS devices.

  • How do I fix CVE-2005-1020?

    To fix CVE-2005-1020, upgrade to a Cisco IOS version that addresses this vulnerability as outlined in Cisco's security advisories.

  • What versions of Cisco IOS are affected by CVE-2005-1020?

    CVE-2005-1020 affects Cisco IOS versions 12.0 through 12.3, including specific releases such as 12.1xg, 12.0xc, and 12.3xr.

  • What type of attack is possible with CVE-2005-1020?

    CVE-2005-1020 allows a remote attacker to trigger a denial of service, leading to a device reload.

  • Is there a workaround for CVE-2005-1020?

    While upgrading the IOS is the primary mitigation, restricting SSH access may provide a temporary workaround for CVE-2005-1020.

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