Debian: 'cron' vulnerability
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Debian The version of Vixie Cron shipped with Debian GNU/Linux 2.2 is vulnerable toa local attack, discovered by Michal Zalewski.

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Debian Security Advisory                                                   Daniel Jacobowitz
November 17, 2000
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Package: cron
Vulnerability: local priviledge escalation
Debian-specific: no
Vulnerable: yes

The version of Vixie Cron shipped with Debian GNU/Linux 2.2 is vulnerable to
a local attack, discovered by Michal Zalewski.  Several problems, including
insecure permissions on temporary files and race conditions in their
deletion, allowed attacks from a denial of service (preventing the editing
of crontabs) to an escalation of priviledge (when another user edited their

As a temporary fix, "chmod go-rx /var/spool/cron/crontabs" prevents the only
available exploit; however, it does not address the problem.  We recommend
upgrading to version 3.0pl1-57.1, for Debian 2.2, or 3.0pl1-61, for Debian

Also, in the new cron packages, it is no longer possible to specify special
files (devices, named pipes, etc.) by name to crontab.  Note that this is
not so much a security fix as a sanity check.

Debian GNU/Linux 2.1 alias slink
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  Slink is no longer being supported by the Debian Security Team.  We highly
  recommend an upgrade to the current stable release.

Debian GNU/Linux 2.2 (stable) alias potato
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  Fixes are currently available for the Alpha, ARM, Intel ia32, Motorola 680x0,
  PowerPC and Sun SPARC architectures, and will be included in 2.2r2.

  Source archives:
      MD5 checksum: 4fac4be2841908090d1c877a65cf5ef9
      MD5 checksum: caed3f1556203618544eec823347df30
      MD5 checksum: 4c64aece846f8483daf440f8e3dd210f

  Alpha architecture:
      MD5 checksum: 3b146f5227182343d3b20cf8fce8a86c

  ARM architecture:
      MD5 checksum: 559e80e83abf371a8d09759ee900daf5

  Intel IA32 architecture:
      MD5 checksum: 922bb72b07a05fb888771364697f52e1

  Motorola 680x0 architecture:
      MD5 checksum: 2e0d8152ec03a66bb88ba84215fe4de3

  PowerPC architecture:
      MD5 checksum: 16ad8c4a26436239e7a25260340be6d5

  Sun Sparc architecture:
      MD5 checksum: 2bd401a635eedc47e9f6dd1652f71e35

Debian GNU/Linux Unstable alias woody
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  This version of Debian is not yet released.

  Fixes will be made available for Alpha, ARM, Intel ia32, Motorola 680x0,
  PowerPC, and SPARC in the Debian archive over the next several days.

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