How severe is CVE-2021-27117?

CVE-2021-27117 has a CVSS score of 7.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2021-27117?

CVE-2021-27117 affects the following packages: github.com/beego/beego/v2 (Go), github.com/beego/beego (Go). Ecosystems affected: Go.

How do I fix CVE-2021-27117?

Update github.com/beego/beego/v2 to 2.0.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-27117 is resolved across your whole dependency graph.

How do I detect CVE-2021-27117 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/beego/beego/v2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-27117 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2021-27117 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2021-27117, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2021-27117?

CVE-2021-27117 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 38th 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-2021-27117?

CVE-2021-27117 is classified as CWE-59 (CWE-59). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2021-27117 published, and has it been updated?

CVE-2021-27117 was published on April 5, 2022 and was last updated on October 24, 2026. 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-2021-27117 — beego

HIGH

CVE-2021-27117 is a high-severity (CVSS 7.8) CWE-59 vulnerability in github.com/beego/beego/v2. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for github.com/beego/beego/v2 — see the affected versions and patch details below.

Privilege escalation in beego

Also known asGHSA-2v6v-q994-xvxx

Published

Apr 5, 2022

Updated

Oct 24, 2026

Affected

2 pkgs

Patched

1 / 2

Exploits

1 known

Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs38th percentile — riskier than 38% of all scored CVEsHighest risk

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

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

2 pkgs affected

🐹github.com/beego/beego/v2🐹github.com/beego/beego

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

beego is an open-source, high-performance web framework for the Go programming language. An issue was discovered in file profile.go in function GetCPUProfile in beego through 2.0.2, allows attackers to launch symlink attacks locally.

Affected Packages

2 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/beego/beego/v2`	≥ 2.0.0&&< 2.0.2	2.0.2`go get github.com/beego/beego/v2@v2.0.2`
🐹Go	`github.com/beego/beego`	all versions	No fix

Affected Products

1 product · 1 configurations

Application

beegobeego

≤ 2.0.2

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

An issue was discovered in file profile.go in function GetCPUProfile in …

github.comNVDApr 2022

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/beego/beego/v2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/beego/beego/v2 to 2.0.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-27117 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2021-27117 in your dependencies?

Find it across Go, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

7.8/10CVSS v3 base

Vector breakdown

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Raw vector

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

CWE Classification

CWE-59CWE-59

Weaponization

No Nuclei template or Metasploit module yet. 1 public proof-of-concept reference is listed on this page.

OpenSSF Scorecard

Package health score

beego

3.6/10

Code-Review8/10

Maintained0/10

Branch-Protection0/10

Assessed Nov 2, 2026

Timeline

Disclosed

Apr 5, 2022

First exploit

Apr 12, 2022

7 days after disclosure — rapid exploitation

Last updated

Oct 24, 2026

Identifiers

CVE-2021-27117

GHSA-2v6v-q994-xvxx

References

Advisorynvd.nist.gov · CVE 2021 27117 Reportgithub.com Packagegithub.com · beego

Related vulnerabilities

This CVE is high severity; 7 of 8 other CVEs affecting v2 are rated as high or higher (top: critical).

CVE-2025-30223CVE-2024-55885CVE-2024-40464CVE-2024-40465CVE-2022-31836CVE-2022-31259CVE-2021-30080CVE-2021-27116

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 24, 2026

CVE-2021-27117 — beego

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-2021-27117 in your dependencies?