Red Hat Enterprise Linux 7 update for nss-softokn

1) Memory-cache side-channel attack

EUVDB-ID: #VU13370

Risk: Low

CVSSv3.1: 3 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:P/RL:O/RC:C]

CVE-ID: CVE-2018-0495

CWE-ID: CWE-200 - Information exposure

Exploit availability: Yes

Description

The vulnerability allows a local attacker to obtain potentially sensitive information.

The vulnerability exists due to a leakage of information through memory caches when the affected library uses a private key to create Elliptic Curve Digital Signature Algorithm (ECDSA) signatures.  A local attacker can conduct a memory-cache side-channel attack on ECDSA signatures and recover sensitive information, such as ECDSA private keys, which could be used to conduct further attacks. 

Note: The vulnerability is known as the "Return Of the Hidden Number Problem" or ROHNP.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux for x86_64 - Extended Update Support: 7.5

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 7.5

Red Hat Enterprise Linux for Power, big endian - Extended Update Support: 7.5

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support: 7.5

nss-softokn (Red Hat package): 3.16.2-1.el7_0 - 3.44.0-8.el7_7

Red Hat Enterprise Linux EUS Compute Node: 7.5

External links

http://access.redhat.com/errata/RHSA-2020:1267

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.

2) Out-of-bounds write

EUVDB-ID: #VU23050

Risk: High

CVSSv3.1: 8.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-11745

CWE-ID: CWE-787 - Out-of-bounds write

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a boundary error when processing untrusted input within the NSC_EncryptUpdate() function in /lib/softoken/pkcs11c.c, when performing padding operations in Mozilla NSS. A remote attacker can pass specially crafted data to the affected application, trigger out-of-bounds write and execute arbitrary code on the target system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Red Hat Enterprise Linux for x86_64 - Extended Update Support: 7.5

Red Hat Enterprise Linux for Power, little endian - Extended Update Support: 7.5

Red Hat Enterprise Linux for Power, big endian - Extended Update Support: 7.5

Red Hat Enterprise Linux for IBM z Systems - Extended Update Support: 7.5

nss-softokn (Red Hat package): 3.16.2-1.el7_0 - 3.44.0-8.el7_7

Red Hat Enterprise Linux EUS Compute Node: 7.5

External links

http://access.redhat.com/errata/RHSA-2020:1267

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.