CVE-2019-1551

MEDIUM

Description

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).

References

http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00030.html

http://packetstormsecurity.com/files/155754/Slackware-Security-Advisory-openssl-Updates.html

https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=419102400a2811582a7a3d4a4e317d72e5ce0a8f

https://git.openssl.org/gitweb/?p=openssl.git;a=commitdiff;h=f1c5eea8a817075d31e43f5876993c6710238c98

https://lists.fedoraproject.org/archives/list/[email protected]/message/DDHOAATPWJCXRNFMJ2SASDBBNU5RJONY/

https://lists.fedoraproject.org/archives/list/[email protected]/message/EXDDAOWSAIEFQNBHWYE6PPYFV4QXGMCD/

https://lists.fedoraproject.org/archives/list/[email protected]/message/XVEP3LAK4JSPRXFO4QF4GG2IVXADV3SO/

https://seclists.org/bugtraq/2019/Dec/39

https://seclists.org/bugtraq/2019/Dec/46

https://security.gentoo.org/glsa/202004-10

https://security.netapp.com/advisory/ntap-20191210-0001/

https://usn.ubuntu.com/4376-1/

https://usn.ubuntu.com/4504-1/

https://www.debian.org/security/2019/dsa-4594

https://www.debian.org/security/2021/dsa-4855

https://www.openssl.org/news/secadv/20191206.txt

https://www.oracle.com/security-alerts/cpujan2021.html

https://www.oracle.com/security-alerts/cpujul2020.html

https://www.tenable.com/security/tns-2019-09

https://www.tenable.com/security/tns-2020-03

https://www.tenable.com/security/tns-2020-11

Details

Source: MITRE

Published: 2019-12-06

Updated: 2021-02-24

Type: CWE-200

Risk Information

CVSS v2.0

Base Score: 5

Vector: AV:N/AC:L/Au:N/C:P/I:N/A:N

Impact Score: 2.9

Exploitability Score: 10

Severity: MEDIUM

CVSS v3.0

Base Score: 5.3

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Impact Score: 1.4

Exploitability Score: 3.9

Severity: MEDIUM