How severe is CVE-2018-20819?

CVE-2018-20819 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-20819 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-20819?

CVE-2018-20819 affects Dropbox Lepton. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-20819?

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

When was CVE-2018-20819 published?

CVE-2018-20819 was published on 2019-04-23 and last updated on 2026-06-17.

CVE-2018-20819

CVE-2018-20819 is a high-severity vulnerability in Dropbox Lepton with a CVSS 3.x base score of 7.8. 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: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Dropbox Lepton
Published: 2019-04-23
Last modified: 2026-06-17

Description

io/ZlibCompression.cc in the decompression component in Dropbox Lepton 1.2.1 allows attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact by crafting a jpg image file. The root cause is a missing check of header payloads that may be (incorrectly) larger than the maximum file size.

Frequently asked questions

What is CVE-2018-20819?: io/ZlibCompression.cc in the decompression component in Dropbox Lepton 1.2.1 allows attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact by crafting a jpg image file. The root cause is a missing check of header payloads that may be (incorrectly) larger than the maximum file size.
How severe is CVE-2018-20819?: CVE-2018-20819 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-20819 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-20819?: CVE-2018-20819 affects Dropbox Lepton. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-20819?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-20819 published?: CVE-2018-20819 was published on 2019-04-23 and last updated on 2026-06-17.

References

https://github.com/dropbox/lepton/issues/112

Affected products (1)

cpe:2.3:a:dropbox:lepton:1.2.1:*:*:*:*:*:*:*

More vulnerabilities in Dropbox Lepton

CVE-2022-26181 — High (CVSS 7.8): Dropbox Lepton v1.2.1-185-g2a08b77 was discovered to contain a heap-buffer-overflow in the function…
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