How severe is CVE-2018-5299?

CVE-2018-5299 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-5299 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-2018-5299?

CVE-2018-5299 primarily affects Pulsesecure Pulse Connect Secure. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-5299?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2018-5299 published?

CVE-2018-5299 was published on 2018-01-16 and last updated on 2026-06-17.

CVE-2018-5299

CVE-2018-5299 is a critical-severity vulnerability in Pulsesecure Pulse Connect Secure with a CVSS 3.x base score of 9.8. 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-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (86th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Pulsesecure Pulse Connect Secure
Published: 2018-01-16
Last modified: 2026-06-17

Description

A stack-based Buffer Overflow Vulnerability exists in the web server in Pulse Secure Pulse Connect Secure (PCS) before 8.3R4 and Pulse Policy Secure (PPS) before 5.4R4, leading to memory corruption and possibly remote code execution.

Frequently asked questions

What is CVE-2018-5299?: A stack-based Buffer Overflow Vulnerability exists in the web server in Pulse Secure Pulse Connect Secure (PCS) before 8.3R4 and Pulse Policy Secure (PPS) before 5.4R4, leading to memory corruption and possibly remote code execution.
How severe is CVE-2018-5299?: CVE-2018-5299 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-5299 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-2018-5299?: CVE-2018-5299 primarily affects Pulsesecure Pulse Connect Secure. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-5299?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-5299 published?: CVE-2018-5299 was published on 2018-01-16 and last updated on 2026-06-17.

References

http://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA43604

Affected products (2)

cpe:2.3:a:pulsesecure:pulse_connect_secure:*:*:*:*:*:*:*:*
cpe:2.3:a:pulsesecure:pulse_policy_secure:*:*:*:*:*:*:*:*

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CVE-2016-4787 — Critical (CVSS 10.0): Pulse Connect Secure (PCS) 8.2 before 8.2r1, 8.1 before 8.1r2, 8.0 before 8.0r10, and 7.4 before 7.4r13.4 allow remote…
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