Vulnerability in Tomwright Dasel
CVE-2026-33320
Dasel is a command-line tool and library for querying, modifying, and transforming data structures. Starting in version 3.0.0 and prior to version 3.3.1, Dasel's YAML reader allows an attacker who can supply YAML for processing to trigger extreme CPU and memory consumption. The issue is in the library's own `UnmarshalYAML` implementation, which manually resolves alias nodes by recursively following `yaml.Node.Alias` pointers without any expansion budget, bypassing go-yaml v4's built-in alias expansion limit. Version 3.3.2 contains a patch for the issue.
EPSS: 0.002 (11.5th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Tomwright Dasel — versions >= 3.0.0, < 3.3.2
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-33320?
- CVE-2026-33320 is a medium-severity vulnerability in Tomwright Dasel, classified under Uncontrolled Recursion. CVSS score: 6.2/10. Published 2026-03-24.
- How severe is CVE-2026-33320?
- Medium severity. CVSS v3 base score is 6.2 out of 10.
- Is CVE-2026-33320 known to be exploited?
- 4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.