CVE-2021-37518

Status: ModifiedMedium (6.1)—
Severity6.1Medium · CVSS 3.1
Exploitation probability0.68 %higher than 52% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

Universal Cross Site Scripting (UXSS) vulnerability in Vimium Extension 1.66 and earlier allows remote attackers to run arbitrary code via omnibar feature.

CVSS

Base score
6.1
Version
3.1
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
0.68 %
Percentile among all scored CVEs
52
Score date
10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

CWEs

References

Show 4 references

Raw JSON (NVD)

Show
{
  "id": "CVE-2021-37518",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2021-37518",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2025-03-26T18:18:47.272878Z"
        }
      }
    ],
    "cvssMetricV31": [
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          "integrityImpact": "LOW",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
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          "privilegesRequired": "NONE",
          "confidentialityImpact": "LOW"
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  "published": "2023-02-03T18:15:13.950",
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      "tags": [
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  "vulnStatus": "Modified",
  "weaknesses": [
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  "descriptions": [
    {
      "lang": "en",
      "value": "Universal Cross Site Scripting (UXSS) vulnerability in Vimium Extension 1.66 and earlier allows remote attackers to run arbitrary code via omnibar feature."
    }
  ],
  "lastModified": "2026-06-17T04:00:40.270",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
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              "versionEndIncluding": "1.66"
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}