CVE-2021-32819

HIGHNVD 8.08.5▲
EchelonGraph scoreHIGH confidence

Score elevated to 8.5 because EPSS predicts 60% probability of exploitation within the next 30 days (top 1.0% of all CVEs). NVD baseline CVSS 8.0 retained for reference. Confidence: see factors.

Triggered by: EPSS exploit prediction ≥85%
Sources: epss, nvd
Elevated
8.5EG
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 58%
CISA-KEV: Not listedEPSS PROB: 58%CVSS: 8.0Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Squirrelly is a template engine implemented in JavaScript that works out of the box with ExpressJS. Squirrelly mixes pure template data with engine configuration options through the Express render API. By overwriting internal configuration options remote code execution may be triggered in downstream applications. This issue is fixed in version 9.0.0. For complete details refer to the referenced GHSL-2021-023.

CVSS v3
8.0
EG Score
8.5(high)
EG Risk
67(Track)
EG Risk 67/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity85% × 45%
Exploitation60% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
58%
EPSS %ILE
99%
KEV
Not listed

Published

May 14, 2021

Last Modified

November 21, 2024

Advisory Details (4)

Auto-updated Sep 21, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit, github_pr.
github🟡 PoC Available

GHSL-2021-023: Remote code execution in squirrelly - CVE-2021-32819 | GitHub Security Lab

https://securitylab.github.com/advisories/GHSL-2021-023-squirrelly/
github_pr Patch Available

[security] Don't use data object for Squirrelly configuration

Patch available: squirrellyjs/squirrelly v9.0.0 (PR #254 merged 2023-05-13)

https://github.com/squirrellyjs/squirrelly/pull/254
github_commit Patch Available

commit dca7a1e7ee91 (squirrellyjs/squirrelly)

Patch available: squirrellyjs/squirrelly v9.0.0 (contains commit dca7a1e7ee91)

https://github.com/squirrellyjs/squirrelly/commit/dca7a1e7ee91d8a6ffffb655f3f15647486db9da
github_commit Patch Available

commit c12418a026f7 (squirrellyjs/squirrelly)

Patch available: squirrellyjs/squirrelly v9.0.0 (contains commit c12418a026f7)

https://github.com/squirrellyjs/squirrelly/commit/c12418a026f73df645ba927fd29358efe02fed1e

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
squirrelly—9.0.0—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 6× in last 7d / 25× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 111 total refreshes for this CVE.

  1. 2026-09-24 14:00 UTCEPSS rescore
  2. 2026-09-23 13:44 UTCEPSS rescore
  3. 2026-09-22 14:44 UTCEPSS rescore
  4. 2026-09-21 20:28 UTCEPSS rescore
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  6. 2026-09-18 19:23 UTCEPSS rescore
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  9. 2026-09-16 14:05 UTCEPSS rescore
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  11. 2026-09-15 03:06 UTCEPSS rescore
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  15. 2026-09-08 21:56 UTCEPSS rescore
  16. 2026-09-06 17:13 UTCOSV refresh
  17. 2026-09-06 13:45 UTCEPSS rescore
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  19. 2026-09-05 15:25 UTCEPSS rescore
  20. 2026-09-04 13:57 UTCEPSS rescore
  21. 2026-09-04 05:03 UTCEPSS rescore
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  24. 2026-08-30 19:14 UTCEPSS rescore
  25. 2026-08-28 21:37 UTCEPSS rescore
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  1. 2026-08-26 14:42 UTCEPSS rescore
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  3. 2026-08-21 23:46 UTCEPSS rescore
  4. 2026-08-20 22:52 UTCEPSS rescore
  5. 2026-08-20 03:34 UTCOSV refresh
  6. 2026-08-19 17:01 UTCEPSS rescore
  7. 2026-08-18 13:45 UTCEPSS rescore
  8. 2026-08-17 13:44 UTCEPSS rescore
  9. 2026-08-16 14:53 UTCEPSS rescore
  10. 2026-08-16 02:11 UTCEPSS rescore
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  13. 2026-08-13 21:57 UTCEPSS rescore
  14. 2026-08-12 13:48 UTCEPSS rescore
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  16. 2026-08-07 16:24 UTCEPSS rescore
  17. 2026-08-06 13:43 UTCEPSS rescore
  18. 2026-08-05 19:14 UTCEPSS rescore
  19. 2026-08-04 22:40 UTCOSV refresh
  20. 2026-07-30 16:25 UTCEPSS rescore
  21. 2026-07-30 01:28 UTCEPSS rescore
  22. 2026-07-28 15:33 UTCEPSS rescore
  23. 2026-07-26 14:52 UTCEPSS rescore
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  25. 2026-07-25 14:15 UTCEPSS rescore
  26. 2026-07-24 14:15 UTCEPSS rescore
  27. 2026-07-23 14:16 UTCEPSS rescore
  28. 2026-07-23 14:16 UTCEPSS rescore
  29. 2026-07-23 02:01 UTCEG score recompute▲ 0.50
  30. 2026-07-22 22:48 UTCEG score recompute▼ 1.00
  31. 2026-07-22 14:06 UTCEPSS rescore
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  33. 2026-07-20 17:05 UTCEPSS rescore
  34. 2026-07-19 14:29 UTCEPSS rescore
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  36. 2026-07-19 02:27 UTCEPSS rescore
  37. 2026-07-18 20:29 UTCOSV refresh
  38. 2026-07-16 17:00 UTCEPSS rescore
  39. 2026-07-16 17:00 UTCEPSS rescore
  40. 2026-07-15 16:55 UTCEPSS rescore
  41. 2026-07-15 01:58 UTCEPSS rescore
  42. 2026-07-13 22:27 UTCEPSS rescore
  43. 2026-07-12 05:44 UTCEPSS rescore
  44. 2026-07-12 05:44 UTCEPSS rescore
  45. 2026-07-11 08:25 UTCEPSS rescore
  46. 2026-07-11 08:25 UTCEPSS rescore
  47. 2026-07-09 19:07 UTCEPSS rescore
  48. 2026-07-07 13:43 UTCEPSS rescore
  49. 2026-07-05 02:28 UTCEPSS rescore
  50. 2026-07-05 02:28 UTCEPSS rescore
  51. 2026-07-01 15:04 UTCEPSS rescore
  52. 2026-07-01 03:18 UTCOSV refresh
  53. 2026-06-28 04:54 UTCEPSS rescore
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  55. 2026-06-27 03:06 UTCEPSS rescore
  56. 2026-06-25 13:48 UTCEPSS rescore
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  58. 2026-06-23 21:31 UTCEPSS rescore
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  60. 2026-06-21 01:58 UTCEPSS rescore
  61. 2026-06-21 01:58 UTCEPSS rescore
  62. 2026-06-18 17:51 UTCEPSS rescore
  63. 2026-06-18 17:51 UTCEPSS rescore
  64. 2026-06-17 17:51 UTCEPSS rescore
  65. 2026-06-16 17:51 UTCEPSS rescore
  66. 2026-06-16 17:51 UTCEPSS rescore
  67. 2026-06-15 17:46 UTCEPSS rescore
  68. 2026-06-13 05:43 UTCOSV refresh
  69. 2026-06-10 22:16 UTCEPSS rescore
  70. 2026-06-10 13:20 UTCEPSS rescore
  71. 2026-06-07 15:23 UTCEPSS rescore
  72. 2026-06-07 15:23 UTCEPSS rescore
  73. 2026-06-06 13:46 UTCEPSS rescore
  74. 2026-06-06 13:46 UTCEPSS rescore
  75. 2026-06-06 13:46 UTCEPSS rescore

Publicly available exploits

(2 references)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCAbady0x1/CVE-2021-32819
    First seen Jun 12, 2021

    SquirrellyJS mixes pure template data with engine configuration options through the Express render API. By overwriting internal configuration options, remote code execution may be triggered in downstream applications.

    Open source ↗
  • Nucleihttp/cves/2021/CVE-2021-32819.yaml
    First seen Jan 1, 2021

    Nodejs Squirrelly - Remote Code Execution

    Open source ↗

Related CVEs(same product + same CWE)

Same product

1 shown

npm:squirrelly

Frequently asked(5)

What is CVE-2021-32819?
CVE-2021-32819 is a high vulnerability published on May 14, 2021. Squirrelly is a template engine implemented in JavaScript that works out of the box with ExpressJS. Squirrelly mixes pure template data with engine configuration options through the Express render API. By overwriting internal configuration options remote code execution may be triggered in…
When was CVE-2021-32819 disclosed?
CVE-2021-32819 was first published in the National Vulnerability Database on May 14, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-32819 actively exploited?
CVE-2021-32819 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 58% probability of exploitation in the next 30 days, which ranks it in the top 0.9% of all scored CVEs.
What is the CVSS score of CVE-2021-32819?
CVE-2021-32819 has a CVSS v3 base score of 8.0 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 8.5.
How do I remediate CVE-2021-32819?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-32819, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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