CVE-2026-63308: Helm Files.Lines Denial of Service via Empty Chart Files
Affects helmSource GCVE Database
Not known to be exploited · CVSS 5.3 Medium : upgrade to 4.2.4 when convenient.
Data as of 30 Oct 2026, 12:22 UTC
Thin evidence
One scorer or none| CNA (VulnCheck) | CVSS 4.0 | 5.3 |
|---|---|---|
| CNA (VulnCheck) | CVSS 3.1 | 4.3 |
- Patch
- Available – fixed in 4.2.4
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:NExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 17 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
CISA SSVC: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by VulnCheck
, 28 hours before disclosure
CVE published
on cve.org
, t = 0
CISA SSVC assessment
proof of concept public
, 1 hour after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA SSVC, the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade helm to 4.2.4.
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Bitnamihelmpkg:bitnami/helmOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade Helm to version 4.2.4 or later, where this vulnerability is fixed. The patch is available and should be applied to prevent exploitation of this denial of service issue.
Description
A denial of service vulnerability exists in Helm versions prior to 4.2.4 in the Files.Lines template helper. This flaw allows attackers to cause an index out of range panic by including empty files in Helm charts, resulting in deterministic render failures during template rendering, installation, upgrade, linting, and SDK Engine.Render operations. The issue is fixed in version 4.2.4.
References
- github.com/helm/helm/commit/ba6c9a29efa7bf9198dad6a5ec12b4fb30c96017 (opens in a new tab)
- github.com/helm/helm/issues/32279 (opens in a new tab)
- github.com/helm/helm/pull/32290 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-63308 (opens in a new tab)
- vulncheck.com/advisories/chat2db-insecure-direct-object-reference-via-get-api-connection-datasource (opens in a new tab)
- vulncheck.com/advisories/helm-files-lines-denial-of-service-via-empty-chart-files (opens in a new tab)