The gnutls_x509_crt_get_serial function in the GnuTLS library before 1.2.1, when running on big-endian, 64-bit platforms, calls the asn1_read_value with a pointer to the wrong data type and the wrong length value, which allows remote attackers to bypass the certificate revocation list (CRL) check and cause a stack-based buffer overflow via a crafted X.509 certificate, related to extraction of a serial number.

From Red Hat Security Advisory 2010:0167 :

Updated gnutls packages that fix two security issues are now available for Red Hat Enterprise Linux 4.

The Red Hat Security Response Team has rated this update as having moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

The GnuTLS library provides support for cryptographic algorithms and for protocols such as Transport Layer Security (TLS).

A flaw was found in the way the TLS/SSL (Transport Layer Security/Secure Sockets Layer) protocols handled session renegotiation. A man-in-the-middle attacker could use this flaw to prefix arbitrary plain text to a client's session (for example, an HTTPS connection to a website). This could force the server to process an attacker's request as if authenticated using the victim's credentials. This update addresses this flaw by implementing the TLS Renegotiation Indication Extension, as defined in RFC 5746.
(CVE-2009-3555)

Refer to the following Knowledgebase article for additional details about the CVE-2009-3555 flaw:
http://kbase.redhat.com/faq/docs/DOC-20491

A flaw was found in the way GnuTLS extracted serial numbers from X.509 certificates. On 64-bit big endian platforms, this flaw could cause the certificate revocation list (CRL) check to be bypassed; cause various GnuTLS utilities to crash; or, possibly, execute arbitrary code. (CVE-2010-0731)

Users of GnuTLS are advised to upgrade to these updated packages, which contain backported patches to correct these issues. For the update to take effect, all applications linked to the GnuTLS library must be restarted, or the system rebooted.

CVE-2009-3555 TLS: MITM attacks via session renegotiation

CVE-2010-0731 gnutls: gnutls_x509_crt_get_serial incorrect serial decoding from ASN1 (BE64) [GNUTLS-SA-2010-1]

A flaw was found in the way the TLS/SSL (Transport Layer Security/Secure Sockets Layer) protocols handled session renegotiation. A man-in-the-middle attacker could use this flaw to prefix arbitrary plain text to a client's session (for example, an HTTPS connection to a website). This could force the server to process an attacker's request as if authenticated using the victim's credentials. This update addresses this flaw by implementing the TLS Renegotiation Indication Extension, as defined in RFC 5746.
(CVE-2009-3555)

Refer to the following Knowledgebase article for additional details about the CVE-2009-3555 flaw:
http://kbase.redhat.com/faq/docs/DOC-20491

Dan Kaminsky found that browsers could accept certificates with MD2 hash signatures, even though MD2 is no longer considered a cryptographically strong algorithm. This could make it easier for an attacker to create a malicious certificate that would be treated as trusted by a browser. GnuTLS now disables the use of the MD2 algorithm inside signatures by default. (CVE-2009-2409) SL5 Only

A flaw was found in the way GnuTLS extracted serial numbers from X.509 certificates. On 64-bit big endian platforms, this flaw could cause the certificate revocation list (CRL) check to be bypassed; cause various GnuTLS utilities to crash; or, possibly, execute arbitrary code. (CVE-2010-0731) SL4 Only

For the update to take effect, all applications linked to the GnuTLS library must be restarted, or the system rebooted.

The remote Redhat Enterprise Linux 4 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2010:0167 advisory.

    The GnuTLS library provides support for cryptographic algorithms and for     protocols such as Transport Layer Security (TLS).

    A flaw was found in the way the TLS/SSL (Transport Layer Security/Secure     Sockets Layer) protocols handled session renegotiation. A man-in-the-middle     attacker could use this flaw to prefix arbitrary plain text to a client's     session (for example, an HTTPS connection to a website). This could force     the server to process an attacker's request as if authenticated using the     victim's credentials. This update addresses this flaw by implementing the     TLS Renegotiation Indication Extension, as defined in RFC 5746.
    (CVE-2009-3555)

    Refer to the following Knowledgebase article for additional details about     the CVE-2009-3555 flaw: http://kbase.redhat.com/faq/docs/DOC-20491

    A flaw was found in the way GnuTLS extracted serial numbers from X.509     certificates. On 64-bit big endian platforms, this flaw could cause the     certificate revocation list (CRL) check to be bypassed; cause various     GnuTLS utilities to crash; or, possibly, execute arbitrary code.
    (CVE-2010-0731)

    Users of GnuTLS are advised to upgrade to these updated packages, which     contain backported patches to correct these issues. For the update to take     effect, all applications linked to the GnuTLS library must be restarted, or     the system rebooted.

Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Updated gnutls packages that fix two security issues are now available for Red Hat Enterprise Linux 4.

The Red Hat Security Response Team has rated this update as having moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

The GnuTLS library provides support for cryptographic algorithms and for protocols such as Transport Layer Security (TLS).

A flaw was found in the way the TLS/SSL (Transport Layer Security/Secure Sockets Layer) protocols handled session renegotiation. A man-in-the-middle attacker could use this flaw to prefix arbitrary plain text to a client's session (for example, an HTTPS connection to a website). This could force the server to process an attacker's request as if authenticated using the victim's credentials. This update addresses this flaw by implementing the TLS Renegotiation Indication Extension, as defined in RFC 5746.
(CVE-2009-3555)

Refer to the following Knowledgebase article for additional details about the CVE-2009-3555 flaw:
http://kbase.redhat.com/faq/docs/DOC-20491

A flaw was found in the way GnuTLS extracted serial numbers from X.509 certificates. On 64-bit big endian platforms, this flaw could cause the certificate revocation list (CRL) check to be bypassed; cause various GnuTLS utilities to crash; or, possibly, execute arbitrary code. (CVE-2010-0731)

Users of GnuTLS are advised to upgrade to these updated packages, which contain backported patches to correct these issues. For the update to take effect, all applications linked to the GnuTLS library must be restarted, or the system rebooted.

ID	Name	Product	Family	Severity
68021	Oracle Linux 4 : gnutls (ELSA-2010-0167)	Nessus	Oracle Linux Local Security Checks	high
60752	Scientific Linux Security Update : gnutls on SL4.x, SL5.x i386/x86_64	Nessus	Scientific Linux Local Security Checks	high
46278	RHEL 4 : gnutls (RHSA-2010:0167)	Nessus	Red Hat Local Security Checks	critical
45366	CentOS 4 : gnutls (CESA-2010:0167)	Nessus	CentOS Local Security Checks	high

Detections

Analytics

CVE-2010-0731

critical

Tenable Plugins

high

high

critical

high