CVE-2019-20851
CVE-2019-20851 is a critical-severity vulnerability in Mattermost with a CVSS 3.x base score of 9.1. 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-22.
Key facts
- Severity: Critical (CVSS 3.x base score 9.1)
- CVSS v2: 6.4
- EPSS exploit prediction: 1% (70th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-22
- Affected product: Mattermost
- Published:
- Last modified:
Description
An issue was discovered in Mattermost Mobile Apps before 1.26.0. An attacker can use directory traversal with the Video Preview feature to overwrite arbitrary files on a device.
Frequently asked questions
- What is CVE-2019-20851?
- An issue was discovered in Mattermost Mobile Apps before 1.26.0. An attacker can use directory traversal with the Video Preview feature to overwrite arbitrary files on a device.
- How severe is CVE-2019-20851?
- CVE-2019-20851 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability high.
- Is CVE-2019-20851 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2019-20851?
- CVE-2019-20851 primarily affects Mattermost. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2019-20851?
- 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-2019-20851 published?
- CVE-2019-20851 was published on 2020-06-19 and last updated on 2026-06-17.
References
Affected products (2)
- cpe:2.3:a:mattermost:mattermost:*:*:*:*:*:android:*:*
- cpe:2.3:a:mattermost:mattermost:*:*:*:*:*:iphone_os:*:*
More vulnerabilities in Mattermost
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- CVE-2024-36492 — High (CVSS 7.4): Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5, 9.8.x <= 9.8.1 fail to disallow the modification of…
All CVEs affecting Mattermost →
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