CVE-2026-62866: CWE-129: Improper Validation of Array Index in TomWright dasel
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.
AI Analysis
Technical Summary
The vulnerability in dasel arises from the parseCurRune function in selector/lexer/tokenize.go, which advances the input index across trailing whitespace without checking for end-of-input before reading the source. When a selector ends with whitespace, including input processed via lexer.NewTokenizer(...).Tokenize() or dasel.Query, this leads to an index-out-of-range panic and process termination. This is an instance of CWE-129: Improper Validation of Array Index. The issue affects versions >=3.0.0 and <3.11.2 and is resolved in version 3.11.2.
Potential Impact
An attacker can cause dasel to crash by providing input selectors ending with whitespace, leading to an index-out-of-range panic and process termination. There is no impact on confidentiality or integrity, but availability is affected due to denial of service.
Mitigation Recommendations
Upgrade dasel to version 3.11.2 or later, where this issue is fixed. No other mitigations are indicated.
CVE-2026-62866: CWE-129: Improper Validation of Array Index in TomWright dasel
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.
CVSS v3.1
Score 6.2medium
Affected software
TomWright
dasel
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in dasel arises from the parseCurRune function in selector/lexer/tokenize.go, which advances the input index across trailing whitespace without checking for end-of-input before reading the source. When a selector ends with whitespace, including input processed via lexer.NewTokenizer(...).Tokenize() or dasel.Query, this leads to an index-out-of-range panic and process termination. This is an instance of CWE-129: Improper Validation of Array Index. The issue affects versions >=3.0.0 and <3.11.2 and is resolved in version 3.11.2.
Potential Impact
An attacker can cause dasel to crash by providing input selectors ending with whitespace, leading to an index-out-of-range panic and process termination. There is no impact on confidentiality or integrity, but availability is affected due to denial of service.
Mitigation Recommendations
Upgrade dasel to version 3.11.2 or later, where this issue is fixed. No other mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-07-14T21:10:50.032Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ab1630f55bf5e2cf5345b94
Added to database: 09/21/2026, 17:02:07 UTC
Last enriched: 09/21/2026, 17:16:35 UTC
Last updated: 09/21/2026, 22:42:52 UTC
Views: 10
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