How severe is CVE-2020-20277?

CVE-2020-20277 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-2020-20277 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 25% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-20277?

CVE-2020-20277 affects Troglobit Uftpd. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-20277?

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-2020-20277 published?

CVE-2020-20277 was published on 2020-12-18 and last updated on 2026-06-17.

CVE-2020-20277

CVE-2020-20277 is a critical-severity vulnerability in Troglobit Uftpd with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 25% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-22.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 25% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-22
Affected product: Troglobit Uftpd
Published: 2020-12-18
Last modified: 2026-06-17

Description

There are multiple unauthenticated directory traversal vulnerabilities in different FTP commands in uftpd FTP server versions 2.7 to 2.10 due to improper implementation of a chroot jail in common.c's compose_abspath function that can be abused to read or write to arbitrary files on the filesystem, leak process memory, or potentially lead to remote code execution.

Frequently asked questions

What is CVE-2020-20277?: There are multiple unauthenticated directory traversal vulnerabilities in different FTP commands in uftpd FTP server versions 2.7 to 2.10 due to improper implementation of a chroot jail in common.c's compose_abspath function that can be abused to read or write to arbitrary files on the filesystem, leak process memory, or potentially lead to remote code execution.
How severe is CVE-2020-20277?: CVE-2020-20277 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-2020-20277 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 25% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-20277?: CVE-2020-20277 affects Troglobit Uftpd. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-20277?: 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-2020-20277 published?: CVE-2020-20277 was published on 2020-12-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:troglobit:uftpd:*:*:*:*:*:*:*:*

More vulnerabilities in Troglobit Uftpd

CVE-2020-20276 — Critical (CVSS 9.8): An unauthenticated stack-based buffer overflow vulnerability in common.c's handle_PORT in uftpd FTP server versions…
CVE-2020-14149 — High (CVSS 7.5): In uftpd before 2.12, handle_CWD in ftpcmd.c mishandled the path provided by the user, causing a NULL pointer…
CVE-2020-5221 — Medium (CVSS 6.5): In uftpd before 2.11, it is possible for an unauthenticated user to perform a directory traversal attack using multiple…
CVE-2020-5204 — Medium (CVSS 6.5): In uftpd before 2.11, there is a buffer overflow vulnerability in handle_PORT in ftpcmd.c that is caused by a buffer…

All CVEs affecting Troglobit Uftpd →

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