Medium severity · published Jun 15, 2018
CVE-2018-12436
wolfcrypt/src/ecc.c in wolfSSL before 3.15.1.patch allows a memory-cache side-channel attack on ECDSA signatures, aka the Return Of the Hidden Number Problem or ROHNP
4.7
CVSS
0.4%
EPSS
No
On KEV
Description
wolfcrypt/src/ecc.c in wolfSSL before 3.15.1.patch allows a memory-cache side-channel attack on ECDSA signatures, aka the Return Of the Hidden Number Problem or ROHNP. To discover an ECDSA key, the attacker needs access to either the local machine or a different virtual machine on the same physical host.
CVSS vector
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
WO
Wolfssl · Wolfssl
before 3.15.3 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-12436
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-12436
Patch
https://github.com/wolfSSL/wolfssl/commit/9b9568d500f31f964af26ba8d01e542e1f27e5ca
Third Party Advisory
https://www.nccgroup.trust/us/our-research/technical-advisory-return-of-the-hidden-number-problem/
Vendor Advisory
https://www.wolfssl.com/wolfssh-and-rohnp/
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