FreeBSD : openssl -- Incorrect PKCS#1 v1.5 padding validation in crypto(3) (077c2dca-8f9a-11db-ab33-000e0c2e438a)

Medium Nessus Plugin ID 23951


The remote FreeBSD host is missing one or more security-related updates.


Problem Description When verifying a PKCS#1 v1.5 signature, OpenSSL ignores any bytes which follow the cryptographic hash being signed. In a valid signature there will be no such bytes. Impact OpenSSL will incorrectly report some invalid signatures as valid. When an RSA public exponent of 3 is used, or more generally when a small public exponent is used with a relatively large modulus (e.g., a public exponent of 17 with a 4096-bit modulus), an attacker can construct a signature which OpenSSL will accept as a valid PKCS#1 v1.5 signature.
Workaround No workaround is available.


Update the affected packages.

See Also

Plugin Details

Severity: Medium

ID: 23951

File Name: freebsd_pkg_077c2dca8f9a11dbab33000e0c2e438a.nasl

Version: $Revision: 1.13 $

Type: local

Published: 2006/12/30

Modified: 2016/05/09

Dependencies: 12634

Risk Information

Risk Factor: Medium


Base Score: 4.3

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N

Temporal Vector: CVSS2#E:ND/RL:OF/RC:C

Vulnerability Information

CPE: p-cpe:/a:freebsd:freebsd:openssl, cpe:/o:freebsd:freebsd

Required KB Items: Host/local_checks_enabled, Host/FreeBSD/release, Host/FreeBSD/pkg_info

Exploit Available: false

Exploit Ease: No known exploits are available

Patch Publication Date: 2006/12/19

Vulnerability Publication Date: 2006/09/06

Reference Information

CVE: CVE-2006-4339

BID: 19849

OSVDB: 28549

FreeBSD: SA-06:19.openssl

CWE: 310