How severe is CVE-2020-8503?

CVE-2020-8503 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-8503 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8503?

CVE-2020-8503 affects Biscom Secure File Transfer. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-8503?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-8503 published?

CVE-2020-8503 was published on 2020-01-31 and last updated on 2026-06-17.

CVE-2020-8503

CVE-2020-8503 is a medium-severity vulnerability in Biscom Secure File Transfer with a CVSS 3.x base score of 6.5. 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-639.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 3.5
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-639
Affected product: Biscom Secure File Transfer
Published: 2020-01-31
Last modified: 2026-06-17

Description

Biscom Secure File Transfer (SFT) 5.0.1050 through 5.1.1067 and 6.0.1000 through 6.0.1003 allows Insecure Direct Object Reference (IDOR) by an authenticated sender because of an error in a file-upload feature. This is fixed in 5.1.1068 and 6.0.1004.

Frequently asked questions

What is CVE-2020-8503?: Biscom Secure File Transfer (SFT) 5.0.1050 through 5.1.1067 and 6.0.1000 through 6.0.1003 allows Insecure Direct Object Reference (IDOR) by an authenticated sender because of an error in a file-upload feature. This is fixed in 5.1.1068 and 6.0.1004.
How severe is CVE-2020-8503?: CVE-2020-8503 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-8503 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8503?: CVE-2020-8503 affects Biscom Secure File Transfer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-8503?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-8503 published?: CVE-2020-8503 was published on 2020-01-31 and last updated on 2026-06-17.

References

https://cve.biscom.com/bis-sft-cv-0008

Affected products (1)

cpe:2.3:a:biscom:secure_file_transfer:*:*:*:*:*:*:*:*

More vulnerabilities in Biscom Secure File Transfer

CVE-2020-8796 — Critical (CVSS 9.8): Biscom Secure File Transfer (SFT) before 5.1.1071 and 6.0.1xxx before 6.0.1005 allows Remote Code Execution on the…
CVE-2016-10710 — High (CVSS 8.1): Biscom Secure File Transfer (SFT) 5.0.1000 through 5.0.1048 does not validate the dataFieldId value, and uses…
CVE-2020-27646 — Medium (CVSS 6.5): Biscom Secure File Transfer (SFT) before 5.1.1082 and 6.x before 6.0.1011 allows user credential theft.
CVE-2017-5247 — Medium (CVSS 5.4): Biscom Secure File Transfer is vulnerable to cross-site scripting in the File Name field. An authenticated user with…
CVE-2017-5241 — Medium (CVSS 5.4): Biscom Secure File Transfer versions 5.0.0.0 trough 5.1.1024 are vulnerable to post-authentication persistent…
CVE-2017-5246 — Medium (CVSS 4.3): Biscom Secure File Transfer is vulnerable to AngularJS expression injection in the Display Name field. An authenticated…

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