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CVE-2021-21391

No known exploitation. EPSS puts it in the 76th percentile. A vendor fix is available.

CVSS 3.16.5MediumEPSS percentile76th1.7% chance in 30 daysCISA KEVNot listedNo confirmed exploitation
No public exploit knownFixVendor fixNo build named by the sources

Published Updated Sources: CVE.org, NVD, GitHub

NVD CVE.org

What to do

The vendor has published a fix. Version details are below where the sources state them.

What it is

From the CVE record

Regular expression Denial of Service in multiple packages

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS76th
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

No public exploit or proof of concept found in the sources we track.

EPSS

1.7% chance of exploitation activity in the next 30 days, which ranks it in the 76th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

5 events over 1302 days, from the signal feeds we watch.

  1. Patch availablerecord updated
  2. Publishedweakness classified, att&ck mapped

Affected products

And 1 more affected product. See all after sign-in

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

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

Scored 6.5 by NVD.

How it is reached

  • Attack Vector NetworkExploitable remotely over the network without any special conditions
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required NoneNo authentication required — anyone can exploit this
  • User Interaction RequiredA user must click a link, open a file, or perform some action

Scope

  • Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

  • Confidentiality NoneNo confidentiality impact
  • Integrity NoneNo integrity impact
  • Availability HighTotal denial of service — the component is completely unavailable

Weaknesses

ATT&CK techniques

Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.

Sources

References in the record

And 16 more references. See all after sign-in

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