How severe is CVE-2018-12437?

CVE-2018-12437 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over physical access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-12437 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-12437?

CVE-2018-12437 primarily affects Libtom Libtomcrypt. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-12437?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-12437 published?

CVE-2018-12437 was published on 2018-06-15 and last updated on 2026-06-17.

CVE-2018-12437

CVE-2018-12437 is a medium-severity vulnerability in Libtom Libtomcrypt with a CVSS 3.x base score of 4.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-200.

Key facts

Severity: Medium (CVSS 3.x base score 4.9)
CVSS v2: 1.9
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Libtom Libtomcrypt
Published: 2018-06-15
Last modified: 2026-06-17

Description

LibTomCrypt through 1.18.1 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.

Frequently asked questions

What is CVE-2018-12437?: LibTomCrypt through 1.18.1 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.
How severe is CVE-2018-12437?: CVE-2018-12437 has a CVSS 3.x base score of 4.9, rated medium severity. It is exploitable over physical access with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-12437 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-12437?: CVE-2018-12437 primarily affects Libtom Libtomcrypt. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-12437?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-12437 published?: CVE-2018-12437 was published on 2018-06-15 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:libtom:libtomcrypt:*:*:*:*:*:*:*:*
cpe:2.3:o:trustedfirmware:op-tee:*:*:*:*:*:*:*:*

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