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NVD / CVE Program· CNA jpcert

CVE-2021-20671: Invalid file validation on the upload feature in GROWI versions v4.2.2 allows a remote attacker with administrative privilege to overwrite t

Noroxi assessment

Priority: Monitor (action score 29/100)

  • 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: 1.9% (FIRST EPSS); higher than 79.8% of all records.
  • Anyone who can reach it over the internet can trigger it. Administrator privileges are required. No user action is required. No special conditions are required; it is repeatable.
  • According to the record, no fixed version is available yet.

Low priority for now. Update when a fix is released; follow the vendor's advisory.

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

Invalid file validation on the upload feature in GROWI versions v4.2.2 allows a remote attacker with administrative privilege to overwrite the files on the server, which may lead to arbitrary code execution.

HighCVSS 7.2 · v3.1—No exploit No fix recorded
Published
Mar 10, 2021
Updated
Jun 16, 2026
EPSS
1.9% · 79th percentile

Report tools

JSON

Action score

29

Monitor

Low priority for now.

CVSS
28 / 40 · 7.2 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 1.9%

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2021-20671

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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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.

VendorProduct
weseekgrowi

Affected versions

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

  • weseek growi4.2.2

Versions reported by the vendor

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

  • WESEEK, Inc. GROWI

    • versions v4.2.2 and earlieraffected

Same product

weseek: all records

Other highest-scoring records for the same primary product.

  • CVE-2021-20736NoSQL injection vulnerability in GROWI versions prior to v4.2.20 allows a remote attacker to obtain and/or alter the information stored in t
    36Monitor
  • CVE-2019-5968Cross-site request forgery (CSRF) vulnerability in GROWI v3.4.6 and earlier allows remote attackers to hijack the authentication of administ
    35Monitor
  • CVE-2020-5683Directory traversal vulnerability in GROWI versions prior to v4.2.3 (v4.2 Series), GROWI versions prior to v4.1.12 (v4.1 Series), and GROWI
    31Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2021-20669Mar 10, 2021 · Path traversal vulnerability in GROWI versions v4.2.2 and earlier allows an attacker with administrator rights to read and/or delete an arbi
    18Monitor
  • ← EarlierCVE-2021-20670Mar 10, 2021 · Improper access control vulnerability in GROWI versions v4.2.2 and earlier allows a remote unauthenticated attacker to read the user's perso
    30Monitor
  • Later →CVE-2021-20672Mar 10, 2021 · Reflected cross-site scripting vulnerability due to insufficient verification of URL query parameters in GROWI (v4.2 Series) versions from v
    24Monitor

Remediation

Which version to upgrade to

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

No fix version is recorded for this entry. Check the references for vendor advisories.

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.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

—

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

  • CVE-2021-20737103 days apartImproper authentication vulnerability in GROWI versions prior to v4.2.20 allows a remote attacker to view the unauthorized pages without acc
    26Monitor

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • Administrator privileges are required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
High
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-20 · Improper Input Validation

CVSS vector

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

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records