# CVE-2026-46377: TomWright Dasel index out of bounds panic in selector lexer

Source: https://junglewise.ai/threats/cve-2026-46377-tomwright-dasel-index-out-of-bounds-panic-in-selector-lexer  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-16. Updated: 2026-07-16  
License: CC BY 4.0 with a link back

CVE-2026-46377 · Severity: high · CVSS 7.5 · Published 2026-07-16

Dasel is a command-line tool and library used for querying and transforming data structures like JSON, YAML, and XML. A vulnerability in how it processes query strings allows an attacker to crash the application by providing a specially crafted query ending in a backslash. This results in a denial-of-service, potentially disrupting automated workflows or web services that rely on the tool to process data.

Technologies: [github.com/tomwright/dasel (Go)](https://junglewise.ai/threats/technologies/github-com-tomwright-dasel), [github.com/tomwright/dasel/v2 (Go)](https://junglewise.ai/threats/technologies/github-com-tomwright-dasel-v2), [github.com/tomwright/dasel/v3 (Go)](https://junglewise.ai/threats/technologies/github-com-tomwright-dasel-v3), [TomWright Dasel](https://junglewise.ai/threats/technologies/dasel). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [TomWright](https://junglewise.ai/threats/vendors/tomwright).

## Quick answers

**Is CVE-2026-46377 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-46377 being exploited in the wild.

**How severe is CVE-2026-46377?** High severity, with a CVSS score of 7.5, published 16 July 2026.

**Which products and versions are affected?** github.com/tomwright/dasel (Go) SEMVER:introduced=0; github.com/tomwright/dasel/v2 (Go) SEMVER:introduced=0; github.com/tomwright/dasel/v3 (Go) >= 3.0.0, <= 3.10.0, SEMVER:introduced=3.0.0, SEMVER:introduced=3.0.0,last_affected=3.10.0; TomWright Dasel >= 3.0.0, < 3.10.1, >= 3.0.0, <= 3.10.0.

**Is there a fix for CVE-2026-46377?** A patch was published on 2026-05-13: Version 3.10.1 released with fix Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-46377 attacked?** It is attacked with local access, in a software library.

**Am I affected by CVE-2026-46377?** Check whether you run github.com/tomwright/dasel (Go), github.com/tomwright/dasel/v2 (Go), github.com/tomwright/dasel/v3 (Go) or one of the others listed at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

An index-out-of-range vulnerability exists in the dasel selector lexer within the `(*Tokenizer).parseCurRune` function in `selector/lexer/tokenize.go`. When the lexer encounters an escape character (backslash) as the final character of a quoted string, it increments the position pointer beyond the source buffer's length and attempts a read without a bounds check. This causes a Go runtime panic. An attacker who can influence the selector or query string passed to dasel can exploit this to cause a denial-of-service (DoS) by crashing the process. The issue is resolved in version 3.10.1 by adding a check for `UnexpectedEOFError`.

## Affected products

- TomWright dasel >= 3.0.0, < 3.10.1

## Identifiers

- CVE-2026-46377
- GHSA-m5j3-4634-c2vq
- GO-2026-5491

## Timeline

- 2026-05-13: advisory: GitHub Security Advisory published
- 2026-05-13: patched: Version 3.10.1 released with fix
- 2026-07-16: disclosed: CVE-2026-46377 published to NVD

## References

- [https://github.com/TomWright/dasel/commit/5fc1172287df89860caf139b146007d7ed12178c](https://github.com/TomWright/dasel/commit/5fc1172287df89860caf139b146007d7ed12178c)
- [https://github.com/TomWright/dasel/releases/tag/v3.10.1](https://github.com/TomWright/dasel/releases/tag/v3.10.1)
- [https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq](https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq)

## Related threats

- [Dasel selector lexer panic on trailing whitespace](https://junglewise.ai/threats/cve-2026-62866-dasel-selector-lexer-panic-on-trailing-whitespace)
- [Dasel unbounded recursion in JSON and XML readers causes stack overflow DoS](https://junglewise.ai/threats/cve-2026-59168-dasel-unbounded-recursion-in-json-and-xml-readers-causes-stack)
- [TomWright Dasel infinite loop in selector lexer](https://junglewise.ai/threats/cve-2026-46378-tomwright-dasel-infinite-loop-in-selector-lexer)
- [Dasel has unbounded YAML alias expansion in dasel leads to CPU/memory denial of service](https://junglewise.ai/threats/cve-2026-33320-dasel-has-unbounded-yaml-alias-expansion-in-dasel-leads-to-cpu)