SynopsisThe remote Debian host is missing one or more security-related updates.
DescriptionThe remote Debian 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the dla-2952 advisory.
- There is an overflow bug in the x64_64 Montgomery squaring procedure used in exponentiation with 512-bit moduli. No EC algorithms are affected. Analysis suggests that attacks against 2-prime RSA1024, 3-prime RSA1536, and DSA1024 as a result of this defect would be very difficult to perform and are not believed likely. Attacks against DH512 are considered just feasible. However, for an attack the target would have to re-use the DH512 private key, which is not recommended anyway. Also applications directly using the low level API BN_mod_exp may be affected if they use BN_FLG_CONSTTIME. Fixed in OpenSSL 1.1.1e (Affected 1.1.1-1.1.1d). Fixed in OpenSSL 1.0.2u (Affected 1.0.2-1.0.2t). (CVE-2019-1551)
- The BN_mod_sqrt() function, which computes a modular square root, contains a bug that can cause it to loop forever for non-prime moduli. Internally this function is used when parsing certificates that contain elliptic curve public keys in compressed form or explicit elliptic curve parameters with a base point encoded in compressed form. It is possible to trigger the infinite loop by crafting a certificate that has invalid explicit curve parameters. Since certificate parsing happens prior to verification of the certificate signature, any process that parses an externally supplied certificate may thus be subject to a denial of service attack. The infinite loop can also be reached when parsing crafted private keys as they can contain explicit elliptic curve parameters. Thus vulnerable situations include: - TLS clients consuming server certificates - TLS servers consuming client certificates - Hosting providers taking certificates or private keys from customers - Certificate authorities parsing certification requests from subscribers - Anything else which parses ASN.1 elliptic curve parameters Also any other applications that use the BN_mod_sqrt() where the attacker can control the parameter values are vulnerable to this DoS issue. In the OpenSSL 1.0.2 version the public key is not parsed during initial parsing of the certificate which makes it slightly harder to trigger the infinite loop. However any operation which requires the public key from the certificate will trigger the infinite loop. In particular the attacker can use a self- signed certificate to trigger the loop during verification of the certificate signature. This issue affects OpenSSL versions 1.0.2, 1.1.1 and 3.0. It was addressed in the releases of 1.1.1n and 3.0.2 on the 15th March 2022. Fixed in OpenSSL 3.0.2 (Affected 3.0.0,3.0.1). Fixed in OpenSSL 1.1.1n (Affected 1.1.1-1.1.1m). Fixed in OpenSSL 1.0.2zd (Affected 1.0.2-1.0.2zc). (CVE-2022-0778)
Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.
SolutionUpgrade the openssl packages.
For Debian 9 stretch, these problems have been fixed in version 1.1.0l-1~deb9u5.
File Name: debian_DLA-2952.nasl
Supported Sensors: Frictionless Assessment Agent, Nessus Agent
Temporal Vector: CVSS2#E:POC/RL:OF/RC:C
Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C
CPE: cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*, p-cpe:2.3:a:debian:debian_linux:libssl-dev:*:*:*:*:*:*:*, p-cpe:2.3:a:debian:debian_linux:openssl:*:*:*:*:*:*:*, p-cpe:2.3:a:debian:debian_linux:libssl-doc:*:*:*:*:*:*:*, p-cpe:2.3:a:debian:debian_linux:libssl1.1:*:*:*:*:*:*:*
Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l
Exploit Ease: Exploits are available
Patch Publication Date: 3/17/2022
Vulnerability Publication Date: 8/22/2019