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% (69th 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% (69th 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
- CVE-2024-39777 — High (CVSS 8.7): Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5 and 9.8.x <= 9.8.1 fail to disallow unsolicited…
- CVE-2024-39274 — High (CVSS 8.7): Mattermost versions 9.9.x <= 9.9.0, 9.5.x <= 9.5.6, 9.7.x <= 9.7.5 and 9.8.x <= 9.8.1 fail to properly validate…
- CVE-2024-39830 — High (CVSS 8.1): Mattermost versions 9.8.x <= 9.8.0, 9.7.x <= 9.7.4, 9.6.x <= 9.6.2 and 9.5.x <= 9.5.5, when shared channels are…
- CVE-2023-3615 — High (CVSS 8.1): Mattermost iOS app fails to properly validate the server certificate while initializing the TLS connection allowing a…
- CVE-2020-13891 — High (CVSS 7.5): An issue was discovered in Mattermost Mobile Apps before 1.31.2 on iOS. Unintended third-party servers could sometimes…
- 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 →
Other CWE-22 (Path Traversal) vulnerabilities
- CVE-2026-48282 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Limitation of a Pathname to a Restricted…
- CVE-2026-54917 — Critical (CVSS 10.0): SeaweedFS is a distributed storage system for object storage (S3), file systems, and Iceberg tables. Prior to 4.30, the…
- CVE-2026-11429 — Critical (CVSS 10.0): Two endpoints in the Vault Service ScriptsController, shared by Altium Enterprise Server and Altium 365, accept file…
- CVE-2026-34909 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit a Path Traversal vulnerability found in UniFi OS devices to…
- CVE-2026-7411 — Critical (CVSS 10.0): In Eclipse BaSyx Java Server SDK versions prior to 2.0.0-milestone-10, inadequate path normalization in the Submodel…
- CVE-2026-36767 — Critical (CVSS 10.0): A path traversal vulnerability in the /content/images/add endpoint of shopizer v3.2.5 allows attackers write arbitrary…