Conectiva Linux Advisory: openssl

Oct 01, 2003, 02:29 (0 Talkback[s])

CONECTIVA LINUX SECURITY ANNOUNCEMENT

PACKAGE	:	openssl
SUMMARY	:	Remote vulnerabilities
DATE	:	2003-09-30 18:40:00
ID	:	CLA-2003:751
RELEVANT RELEASES	:	7.0, 8, 9

DESCRIPTION
OpenSSL[1] implements the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) protocols as well as full-strength general purpose cryptography functions. It is used (as a library) by several projects, like Apache, OpenSSH, Bind, OpenLDAP and many others clients and servers programs.

NISCC[2] developed a test suit to verify the behavior of SSL and TLS implementations when presented with malformed client certificates. As a result of this test, the following vulnerabilities[3,4] were found in the OpenSSL implementation:

Vulnerabilities in the handling of malformed ASN.1 tags (CAN-2003-0543[5] and CAN-2003-0544[6]). Because of a flaw in the handling of ASN.1 tag values, an out-of-bounds read can be triggered in some situations. A remote attacker can exploit these vulnerabilities to cause a denial of service condition.
Stack corruption in the handling of rejected ASN.1 encodings (CAN-2003-0545[7]). A remote attacker may exploit this vulnerability to cause a denial of service condition and potentially execute arbitrary code. This vulnerability does not affect the OpenSSL versions distributed with Conectiva Linux 7.0 and 8 (OpenSSL-0.9.6).

Additionally, this update includes fixes for a bug which causes OpenSSL to parse a client certificate when it should reject it as a protocol error.

SOLUTION
It is recommended that all users upgrade their openssl packages.

Please note that it is necessary to restart services which use the library (such as the apache web server with SSL enabled) so that the new, fixed, version is used. A list of such applications can be obtained after the upgrade with the following command:

lsof | grep libssl

The first column will contain the name of the application that needs to be restarted. If there is any doubt about which application has to be restarted or how to do it, we recommend that the system be rebooted.

REFERENCES
1.http://www.openssl.org
2.http://www.niscc.gov.uk/aboutniscc/index.htm
3.http://www.uniras.gov.uk/vuls/2003/006489/openssl.htm
4.http://www.openssl.org/news/secadv_20030930.txt
5.http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0543
6.http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0544
7.http://cve.mitre.org/cgi-bin/cvename.cgi?name=CAN-2003-0545

ADDITIONAL INSTRUCTIONS
The apt tool can be used to perform RPM packages upgrades:

run: apt-get update
after that, execute: apt-get upgrade

Detailed instructions reagarding the use of apt and upgrade examples can be found at http://distro.conectiva.com.br/atualizacoes/#apt?idioma=en

All packages are signed with Conectiva's GPG key. The key and instructions on how to import it can be found at
http://distro.conectiva.com.br/seguranca/chave/?idioma=en Instructions on how to check the signatures of the RPM packages can be found at http://distro.conectiva.com.br/seguranca/politica/?idioma=en

All our advisories and generic update instructions can be viewed at http://distro.conectiva.com.br/atualizacoes/?idioma=en

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Conectiva Linux Advisory: openssl