BSD-derived telnetd options telrcv buffer overflow (Telnet_Too_Many_AYTs)

For vulnerability detection:

Enable the following checks in the ISS Protection Platform:
TelnetdOptionTelrcvBo
telnetd-option-telrcv-bo

For Virtual Patch:

Enable the following checks in the ISS Protection Platform:
Telnet_Too_Many_AYTs

Block or restrict the following in the ISS Protection Platform as appropriate to the environment:
Port 23

For Manual Protection:

For FreeBSD 3.x, versions prior to 4.3, and 4.3-STABLE:
Upgrade to the latest version of FreeBSD (4.3-STABLE dated 2001-07-23 or later), as listed in FreeBSD Security Advisory FreeBSD-SA-01:49. See References.

— OR —

Apply the patch for this vulnerability, as listed in FreeBSD Security Advisory FreeBSD-SA-01:49. See References.

For Caldera OpenLinux 2.3, eServer 2.3.1, eBuilder, eDesktop 2.4, Server 3.1, and Workstation 3.1:
Upgrade to the latest version of netkit-telnet (0.17-12a or later), as listed in Caldera International, Inc. Security Advisory CSSA-2001-030.0. See References.

For Mandrake Linux 7.1 and Corporate Server 1.0.1:
Upgrade to the latest version of telnet (0.16-4 or later), as listed in MandrakeSoft Security Advisory MDKSA-2001:068 : telnet. See References.

For Mandrake Linux 7.2, 8.0, and Single Network Firewall 7.2:
Upgrade to the latest version of telnet (0.17-7 or later), as listed in MandrakeSoft Security Advisory MDKSA-2001:068 : telnet. See References.

For Mandrake Linux 8.1:
Upgrade to the latest version of krb5 (1.2.2-15.1mdk or later), as listed in MandrakeSoft Security Advisory MDKSA-2001:093 : krb5. See References.

For Debian GNU/Linux 2.2 (potato):
Upgrade to the latest version of netkit-telnet (0.16-4potato.2 or later), as listed in DSA-070-1. See References.

For Debian GNU/Linux 2.2 (potato):
Upgrade to the latest version of netkit-telnet-ssl (0.16.3-1.1 or later), as listed in DSA-075-1. See References.

For Red Hat Linux 5.2 and 6.2:
Upgrade to the latest version of telnet (0.17.6x-18 or later), as listed in RHSA-2001:099-06. See References.

For Red Hat Linux 7.0 and 7.1
Upgrade to the latest version of telnet (0.17-18 or later), as listed in RHSA-2001:099-06. See References.

For MIT Kerberos 5:
Apply the telnetd_122_patch for your system, as listed in Kerberos Security Advisory 2001-07-31. See References.

For Red Hat Linux 6.2 using the Kerberos 5 package telnet server:
Upgrade to the latest version of krb5 (1.1.1-28 or later), as listed in RHSA-2001:100-02. See References.

For Red Hat Linux 7.0 and 7.1 using the Kerberos 5 package telnet server:
Upgrade to the latest version of krb5 (1.2.2-12 or later), as listed in RHSA-2001:100-02. See References.

For Conectiva Linux 4.0 and 4.0es:
Upgrade to the latest version of telnet (0.17-1U40 or later), as listed in Conectiva Linux Security Announcement CLA-2001:413. See References.

For Conectiva Linux 4.1:
Upgrade to the latest version of telnet (0.17-1U41 or later), as listed in Conectiva Linux Security Announcement CLA-2001:413. See References.

For Conectiva Linux 4.2:
Upgrade to the latest version of telnet (0.17-1U42 or later), as listed in Conectiva Linux Security Announcement CLA-2001:413. See References.

For Conectiva Linux 5.0, ecommerce, and prg graficos:
Upgrade to the latest version of telnet (0.17-1U50 or later), as listed in Conectiva Linux Security Announcement CLA-2001:413. See References.

For Conectiva Linux 5.1:
Upgrade to the latest version of telnet (0.17-1U51 or later), as listed in Conectiva Linux Security Announcement CLA-2001:413. See References.

For Conectiva Linux 6.0:
Upgrade to the latest version of telnet (0.17-2U60 or later), as listed in Conectiva Linux Security Announcement CLA-2001:413. See References.

For Conectiva Linux 7.0:
Upgrade to the latest version of telnet (0.17-2U70 or later), as listed in Conectiva Linux Security Announcement CLA-2001:413. See References.

For SuSE Linux 7.0 (i386 Intel, Sparc, AXP Alpha, and PPC Power PC):
Upgrade to the latest version of nkitb or nkitserv (2001.8.16-0 or later), as listed in SuSE Security Announcement SuSE-SA:2001:029. See References.

For SuSE Linux 7.1 (i386 Intel, Sparc, AXP Alpha, and PPC Power PC):
Upgrade to the latest version of nkitb or nkitserv (2001.8.14-0 or later), as listed in SuSE Security Announcement SuSE-SA:2001:029. See References.

For SuSE Linux 7.2 (i386 Intel):
Upgrade to the latest version of telnet or telnet-server (1.0-69 or later), as listed in SuSE Security Announcement SuSE-SA:2001:029. See References.

For Cisco Catalyst 6000 series, Catalyst 5000 series, Catalyst 4000 series, Catalyst 2948G, and Catalyst 2900 switches:
Upgrade to the latest version of CatOS for your device, as listed in the Cisco Security Advisory dated January 29, 2002. See References.

For Cisco VPN 3000 Concentrators:
Upgrade to the latest software version for your device (3.6.1 or later), (3.5.5 or later), (3.1.2 or later for 3.1.x releases), or (3.0.3(B) or later for 3.0.x releases), as listed in Cisco Security Advisory: Cisco VPN 3000 Concentrator Multiple Vulnerabilities. See References.

For Gentoo Linux: Upgrade to the latest version of NetKit (0.17-r4 or later), as listed in GLSA 200410-03. See References.

For other distributions:
Contact your vendor for patch or upgrade information.