How severe is CVE-2019-15551?

CVE-2019-15551 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-2019-15551 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-15551?

CVE-2019-15551 affects Servo Smallvec. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-15551?

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-2019-15551 published?

CVE-2019-15551 was published on 2019-08-26 and last updated on 2026-06-17.

CVE-2019-15551

CVE-2019-15551 is a critical-severity vulnerability in Servo Smallvec 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-415.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-415
Affected product: Servo Smallvec
Published: 2019-08-26
Last modified: 2026-06-17

Description

An issue was discovered in the smallvec crate before 0.6.10 for Rust. There is a double free for certain grow attempts with the current capacity.

Frequently asked questions

What is CVE-2019-15551?: An issue was discovered in the smallvec crate before 0.6.10 for Rust. There is a double free for certain grow attempts with the current capacity.
How severe is CVE-2019-15551?: CVE-2019-15551 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-2019-15551 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-15551?: CVE-2019-15551 affects Servo Smallvec. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-15551?: 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-2019-15551 published?: CVE-2019-15551 was published on 2019-08-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:servo:smallvec:*:*:*:*:*:*:*:*

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