Vulnerability · Published Sep 21, 2026 · Assigned by GitHub_M
CVE-2026-62866Dasel: Selector lexer panics on trailing whitespace in `parseCurRune`
Medium 6.2
In plain English
A medium-severity security flaw in dasel from TomWright. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 9% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Dasel is a command-line tool and library for querying, modifying, and transforming data structures. From 3.0.0 until 3.11.2, selector/lexer/tokenize.go parseCurRune advances the input index across trailing whitespace and then reads the source at the exhausted index without an end-of-input check. A selector ending in whitespace, including input passed through lexer.NewTokenizer(...).Tokenize() or dasel.Query, can therefore cause an index-out-of-range panic and terminate the process. This issue is fixed in version 3.11.2.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:14 | dasel | 3.11.2-1 | DEBIAN-CVE-2026-62866 |
| Go | github.com/tomwright/dasel | no fix listed | GO-2026-6548 |
| Go | github.com/tomwright/dasel/v2 | no fix listed | GO-2026-6548 |
| Go | github.com/tomwright/dasel/v3 | 3.11.2 | GHSA-65gg-g7rw-6cpc |
| Go | github.com/tomwright/dasel/v3 | 3.11.2 | GO-2026-6548 |
| Ubuntu:26.04:LTS | dasel | no fix listed | UBUNTU-CVE-2026-62866 |
| Ubuntu:26.10 | dasel | no fix listed | UBUNTU-CVE-2026-62866 |
Affected products (as reported)
Weakness: CWE-129 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/TomWright/dasel/security/advisories/GHSA-65gg-g7rw-6cpc x_refsource_CONFIRM
- https://github.com/TomWright/dasel/commit/eee03aec28d4a33d6138098d065b7b37b85e3c55 x_refsource_MISC
- https://github.com/TomWright/dasel/releases/tag/v3.11.2 x_refsource_MISC