How severe is CVE-2018-5389?

CVE-2018-5389 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-5389 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-5389?

CVE-2018-5389 affects Ietf Internet Key Exchange. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-5389?

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

When was CVE-2018-5389 published?

CVE-2018-5389 was published on 2018-09-06 and last updated on 2026-06-17.

CVE-2018-5389

CVE-2018-5389 is a medium-severity vulnerability in Ietf Internet Key Exchange with a CVSS 3.x base score of 5.9. 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-521.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-521
Affected product: Ietf Internet Key Exchange
Published: 2018-09-06
Last modified: 2026-06-17

Description

The Internet Key Exchange v1 main mode is vulnerable to offline dictionary or brute force attacks. Reusing a key pair across different versions and modes of IKE could lead to cross-protocol authentication bypasses. It is well known, that the aggressive mode of IKEv1 PSK is vulnerable to offline dictionary or brute force attacks. For the main mode, however, only an online attack against PSK authentication was thought to be feasible. This vulnerability could allow an attacker to recover a weak Pre-Shared Key or enable the impersonation of a victim host or network.

Frequently asked questions

What is CVE-2018-5389?: The Internet Key Exchange v1 main mode is vulnerable to offline dictionary or brute force attacks. Reusing a key pair across different versions and modes of IKE could lead to cross-protocol authentication bypasses. It is well known, that the aggressive mode of IKEv1 PSK is vulnerable to offline dictionary or brute force attacks. For the main mode, however, only an online attack against PSK authentication was thought to be feasible. This vulnerability could allow an attacker to recover a weak Pre-Shared Key or enable the impersonation of a victim host or network.
How severe is CVE-2018-5389?: CVE-2018-5389 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-5389 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-5389?: CVE-2018-5389 affects Ietf Internet Key Exchange. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-5389?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-5389 published?: CVE-2018-5389 was published on 2018-09-06 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:ietf:internet_key_exchange:1.0:*:*:*:*:*:*:*

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