How severe is CVE-2020-26171?

CVE-2020-26171 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2020-26171 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-26171?

CVE-2020-26171 affects Tangro Business Workflow. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-26171?

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

When was CVE-2020-26171 published?

CVE-2020-26171 was published on 2020-12-18 and last updated on 2026-06-17.

CVE-2020-26171

CVE-2020-26171 is a medium-severity vulnerability in Tangro Business Workflow with a CVSS 3.x base score of 4.3. 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 4.3)
CVSS v2: 4.0
EPSS exploit prediction: 1% (43rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-639
Affected product: Tangro Business Workflow
Published: 2020-12-18
Last modified: 2026-06-17

Description

In tangro Business Workflow before 1.18.1, the documentId of attachment uploads to /api/document/attachments/upload can be manipulated. By doing this, users can add attachments to workitems that do not belong to them.

Frequently asked questions

What is CVE-2020-26171?: In tangro Business Workflow before 1.18.1, the documentId of attachment uploads to /api/document/attachments/upload can be manipulated. By doing this, users can add attachments to workitems that do not belong to them.
How severe is CVE-2020-26171?: CVE-2020-26171 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2020-26171 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-26171?: CVE-2020-26171 affects Tangro Business Workflow. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-26171?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-26171 published?: CVE-2020-26171 was published on 2020-12-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:tangro:business_workflow:*:*:*:*:*:*:*:*

More vulnerabilities in Tangro Business Workflow

CVE-2020-26174 — High (CVSS 8.8): tangro Business Workflow before 1.18.1 requests a list of allowed filetypes from the server and restricts uploads to…
CVE-2020-26175 — Medium (CVSS 6.5): In tangro Business Workflow before 1.18.1, an attacker can manipulate the value of PERSON in requests to /api/profile…
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CVE-2020-26177 — Medium (CVSS 4.3): In tangro Business Workflow before 1.18.1, a user's profile contains some items that are greyed out and thus are not…
CVE-2020-26176 — Medium (CVSS 4.3): An issue was discovered in tangro Business Workflow before 1.18.1. No (or broken) access control checks exist on the…
CVE-2020-26172 — Medium (CVSS 4.2): Every login in tangro Business Workflow before 1.18.1 generates the same JWT token, which allows an attacker to reuse…

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