CVE-2026-12644

MEDIUMPre-NVD 5.35.3—
EchelonGraph scoreHIGH confidence

Score 5.3 from GitHub Security Advisory published 2026-06-19. a secondary CVSS source baseline 5.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
5.3
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.3Exploit: NoneExposed: 0

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

Versions of the package ts-deepmerge before 8.0.0 are vulnerable to Uncaught Exception due to the improper handling of built-in Object.prototype methods (such as toString, valueOf). When user-controlled input contains these keys with non-function values, the resulting merged object becomes broken — any string context operation throws a TypeError, crashing the application.

CVSS v3
5.3
EG Score
5.3(high)
EPSS
22.6%
KEV
Not listed

Published

June 19, 2026

Last Modified

June 23, 2026

Advisory Details (3)

Auto-updated Jun 22, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit.
generic

ts-deepmerge-prototype-method-override.md · GitHub

https://gist.github.com/igorg1312/775fa00114c4d47df6ae0551779ab407
generic🟡 PoC Available

Uncaught Exception in ts-deepmerge | CVE-2026-12644 | Snyk

https://security.snyk.io/vuln/SNYK-JS-TSDEEPMERGE-17339141
github_commit Patch Available

commit 305a05831a46 (voodoocreation/ts-deepmerge)

Patch available: voodoocreation/ts-deepmerge 8.0.0 (contains commit 305a05831a46)

https://github.com/voodoocreation/ts-deepmerge/commit/305a05831a462fb2c353d3cbbff55a0733286f8c

Vendor Advisories for CVE-2026-12644(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFixed inDependents
ts-deepmerge—8.0.0—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 15× in last 7d / 36× 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.

  1. 2026-07-06 16:27 UTCEPSS rescore
  2. 2026-07-06 14:07 UTCEG score recompute
  3. 2026-07-06 02:23 UTCEPSS rescore
  4. 2026-07-05 13:48 UTCEG score recompute
  5. 2026-07-05 02:30 UTCEPSS rescore
  6. 2026-07-05 02:30 UTCEPSS rescore
  7. 2026-07-04 13:33 UTCEG score recompute
  8. 2026-07-04 06:31 UTCEPSS rescore
  9. 2026-07-03 13:17 UTCEG score recompute
  10. 2026-07-02 13:02 UTCEG score recompute
  11. 2026-07-01 15:06 UTCEPSS rescore
  12. 2026-07-01 15:06 UTCEPSS rescore
  13. 2026-07-01 12:45 UTCEG score recompute
  14. 2026-06-30 23:22 UTCEPSS rescore
  15. 2026-06-30 12:30 UTCEG score recompute
  16. 2026-06-29 14:06 UTCEPSS rescore
  17. 2026-06-29 12:07 UTCEG score recompute
  18. 2026-06-28 14:07 UTCEPSS rescore
  19. 2026-06-28 11:52 UTCEG score recompute
  20. 2026-06-28 04:56 UTCEPSS rescore
  21. 2026-06-28 04:56 UTCEPSS rescore
  22. 2026-06-27 11:37 UTCEG score recompute
  23. 2026-06-27 03:08 UTCEPSS rescore
  24. 2026-06-26 11:23 UTCEG score recompute
  25. 2026-06-25 13:49 UTCEPSS rescore
Show 11 more
  1. 2026-06-25 08:35 UTCEG score recompute
  2. 2026-06-24 14:05 UTCEPSS rescore
  3. 2026-06-24 08:21 UTCEG score recompute
  4. 2026-06-23 21:32 UTCEPSS rescore
  5. 2026-06-23 08:06 UTCEG score recompute
  6. 2026-06-22 17:37 UTCNVD updateCVSS v4 → 5.5
  7. 2026-06-22 07:45 UTCEG score recompute
  8. 2026-06-21 07:27 UTCEG score recompute
  9. 2026-06-20 07:13 UTCEG score recompute
  10. 2026-06-19 06:56 UTCEG score recompute
  11. 2026-06-19 06:56 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-12644?
CVE-2026-12644 is a medium vulnerability published on June 19, 2026. Versions of the package ts-deepmerge before 8.0.0 are vulnerable to Uncaught Exception due to the improper handling of built-in Object.prototype methods (such as toString, valueOf). When user-controlled input contains these keys with non-function values, the resulting merged object becomes broken —…
When was CVE-2026-12644 disclosed?
CVE-2026-12644 was first published in the National Vulnerability Database on June 19, 2026, with the most recent update on June 23, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-12644 actively exploited?
CVE-2026-12644 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 22.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-12644?
CVE-2026-12644 has a CVSS v3 base score of 5.3 (NVD).
How do I remediate CVE-2026-12644?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-12644, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-12644

Explore →

Is Your Infrastructure Affected by CVE-2026-12644?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs