Debian Security Advisory

DSA-1195-1 openssl096 -- denial of service (multiple)

Date Reported:
10 Oct 2006
Affected Packages:
Security database references:
In Mitre's CVE dictionary: CVE-2006-2940, CVE-2006-3738, CVE-2006-4343.
More information:

Multiple vulnerabilities have been discovered in the OpenSSL cryptographic software package that could allow an attacker to launch a denial of service attack by exhausting system resources or crashing processes on a victim's computer.

  • CVE-2006-3738

    Tavis Ormandy and Will Drewry of the Google Security Team discovered a buffer overflow in SSL_get_shared_ciphers utility function, used by some applications such as exim and mysql. An attacker could send a list of ciphers that would overrun a buffer.

  • CVE-2006-4343

    Tavis Ormandy and Will Drewry of the Google Security Team discovered a possible DoS in the sslv2 client code. Where a client application uses OpenSSL to make a SSLv2 connection to a malicious server that server could cause the client to crash.

  • CVE-2006-2940

    Dr S N Henson of the OpenSSL core team and Open Network Security recently developed an ASN1 test suite for NISCC ( When the test suite was run against OpenSSL a DoS was discovered.

    Certain types of public key can take disproportionate amounts of time to process. This could be used by an attacker in a denial of service attack.

For the stable distribution (sarge) these problems have been fixed in version 0.9.6m-1sarge4.

This package exists only for compatibility with older software, and is not present in the unstable or testing branches of Debian.

We recommend that you upgrade your openssl096 package. Note that services linking against the openssl shared libraries will need to be restarted. Common examples of such services include most Mail Transport Agents, SSH servers, and web servers.

Fixed in:

Debian GNU/Linux 3.1 (sarge)

HP Precision:
Intel IA-32:
Intel IA-64:
Motorola 680x0:
Big-endian MIPS:
Little-endian MIPS:
IBM S/390:
Sun Sparc:

MD5 checksums of the listed files are available in the original advisory.