NVD / CVE Program· CNA GitHub_M

CVE-2021-21250: Post-Auth External Entity Expansion (XXE)

MediumCVSS 6.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 26/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.94% (FIRST EPSS); higher than 61.4% of all records.
Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
Fixed version: theonedev onedev 4.0.3.

Low priority for now. Upgrade to theonedev onedev 4.0.3 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

OneDev is an all-in-one devops platform. In OneDev before version 4.0.3, there is a critical vulnerability which may lead to arbitrary file read. When BuildSpec is provided in XML format, the spec is processed by XmlBuildSpecMigrator.migrate(buildSpecString); which processes the XML document without preventing the expansion of external entities. These entities can be configured to read arbitrary files from the file system and dump their contents in the final XML document to be migrated. If the files are dumped in properties included in the YAML file, it will be possible for an attacker to read them. If not, it is possible for an attacker to exfiltrate the contents of these files Out Of Band. This issue was addressed in 4.0.3 by ignoring ENTITY instructions in xml file.

Published: Jan 15, 2021
Updated: Jun 16, 2026
EPSS: 0.9% · 61th percentile
CWE: CWE-538

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 26 / 40 · 6.5 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.9%

CNA vs NVD score

NVD: 6.5
CNA · GitHub_M: 7.7; 1.2 point gap

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

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No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
onedev project	onedev	cpe:2.3:a:onedev_project:onedev

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

theonedev onedev
- < 4.0.3affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

onedev project onedevbefore 4.0.3

Same product

onedev project: all records

Other highest-scoring records for the same primary product.

CVE-2021-21242Pre-Auth Unsafe Deserialization on AttachmentUploadServet
61This week
CVE-2024-45309OneDev vulnerable to arbitrary file reading for unauthenticated user
60This week
CVE-2021-21243Pre-Auth Unsafe Deserialization on KubernetesResource
55Plan

Published before and after this one in the same product

← EarlierCVE-2021-21248Jan 15, 2021 · Post-Auth Arbitrary Code execution via Groovy script injection
35Monitor
← EarlierCVE-2021-21249Jan 15, 2021 · Post-Auth Unsafe Yaml deserialization
36Monitor
Later →CVE-2021-21251Jan 15, 2021 · ZipSlip Arbitrary File Upload
39Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
theonedev onedev	4.0.3 · description	Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.