How severe is CVE-2021-21501?

CVE-2021-21501 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2021-21501?

CVE-2021-21501 affects the following packages: github.com/apache/servicecomb-service-center (Go). Ecosystems affected: Go.

How do I fix CVE-2021-21501?

Update github.com/apache/servicecomb-service-center to 2.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-21501 is resolved across your whole dependency graph.

How do I detect CVE-2021-21501 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/apache/servicecomb-service-center, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-21501 if there is no patch (or I can't update yet)?

Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Is CVE-2021-21501 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-21501 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2021-21501?

CVE-2021-21501 has an EPSS (Exploit Prediction Scoring System) score of 4.4%, placing it in the 91th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2021-21501?

CVE-2021-21501 is classified as Path Traversal (CWE-22). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2021-21501 published, and has it been updated?

CVE-2021-21501 was published on September 1, 2021 and was last updated on November 8, 2023. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹

🐹 Go

Not in CISA KEV

HIGH severity

CVE-2021-21501 — servicecomb-service-center

HIGHFix: apache/servicecomb-service-center#788

CVE-2021-21501 is a high-severity (CVSS 7.5) Path Traversal vulnerability in github.com/apache/servicecomb-service-center. A fix is available for github.com/apache/servicecomb-service-center — see the affected versions and patch details below.

Path traversal in ServiceCenter

Published

Sep 1, 2021

Updated

Nov 8, 2023

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

4.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs91th percentile — riskier than 91% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2021-21501 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 385,386 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

1 pkg affected

🐹github.com/apache/servicecomb-service-center

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Improper configuration will cause ServiceComb ServiceCenter Directory Traversal problem in ServcieCenter 1.x.x versions and fixed in 2.0.0.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/apache/servicecomb-service-center`	all versions	2.0.0`go get github.com/apache/servicecomb-service-center@v2.0.0`

Affected Products

1 product · 1 configurations

Application

servicecombapache

≥ 1.0.0 && < 2.0.0

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/apache/servicecomb-service-center, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/apache/servicecomb-service-center to 2.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-21501 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Frequently Asked Questions

Improper configuration will cause ServiceComb ServiceCenter Directory Traversal problem in ServcieCenter 1.x.x versions and fixed in 2.0.0.

O3 Security · Impact-Aware SCA

Is CVE-2021-21501 in your dependencies?

Find it across Go, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

7.5/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Raw vector

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

CWE Classification

CWE-22Path Traversal

Weaponization

No known public exploit tooling found.

Timeline

Disclosed

Sep 1, 2021

Last updated

Nov 8, 2023

Identifiers

CVE-2021-21501

References

Advisorynvd.nist.gov Webgithub.com Webgithub.com Weblists.apache.org Webopenwall.com Packagegithub.com

Related vulnerabilities

Also affects servicecomb-service-center

This CVE is high severity; 1 of 2 other CVEs affecting servicecomb-service-center is rated as high or higher (top: high).

CVE-2023-44313CVE-2023-44312

Same weakness: CWE-22

This CVE is high severity; 4 of 6 other CVEs with CWE-22 are rated as high or higher (top: critical).

CVE-2026-63445CVE-2026-72697CVE-2026-74907CVE-2026-63225CVE-2026-86071CVE-2026-45140Browse all CWE-22

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedNov 8, 2023

CVE-2021-21501 — servicecomb-service-center

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Frequently Asked Questions

Is CVE-2021-21501 in your dependencies?