Vulnerability-Lookup

FKIE_CVE-2026-95834

Vulnerability from fkie_nvd - Published: 2026-09-25 17:17 - Updated: 2026-09-25 17:17

Severity

4.6 (Medium) - CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N

Summary

Use After Free in the drag source path of the drag and drop protocol in kitty from 0.47.0 before 0.49.0 allows a program writing to the terminal to cause the terminal to read from and write to freed heap memory, because drag_remote_file_data() in kitty/dnd.c holds a DragRemoteItem pointer into an array it does not own, calls toplevel_data_for_drag() or subdir_data_for_drag(), and then continues to use that pointer. Those helpers, and add_payload() and populate_dir_entries() which they call, report errors through the abrt() macro, which expands to cancel_drag() followed by a plain return, and cancel_drag() calls drag_free_offer(), which frees the array the pointer refers to. The helpers return void, so the caller receives no indication that the teardown happened, and proceeds to call all_children_complete() on the freed pointer, which dereferences it, and then to write through it. That dereference is guarded by a local flag that is set when the request carries no payload and announces no further data, which is the same condition that selects the finalisation block of add_payload(), so the error paths in that block reach it: a create that fails because an entry of the same name already exists, because the client may declare two entries with one name and the create operations use O_CREAT with O_EXCL and symlinkat(), a mkdirat() failure other than EEXIST, and the directory entry allocation paths. Both branches reach it. In the top level branch the caller's pointer is never cleared, so clearing the owning structure's own pointers during teardown does not help. In the sub directory branch subdir_data_for_drag() sets the caller's pointer to NULL on entry and assigns it only after its own last error path, so its own aborts leave the caller with NULL and are stopped by a null check, but it then calls add_payload() with that pointer set, and an abort there leaves the caller holding a freed child node inside the item tree, which drag_free_offer() frees by recursion. This results in undefined behaviour in the terminal process, reachable from the byte stream of any program running in the window.

References

	URL	Tags
	4daa8cea-433a-44bd-9456-53b127fc289a	https://github.com/kovidgoyal/kitty/commit/b54bfbb4f85f992edca9b04f5c0c2612454eec23
	4daa8cea-433a-44bd-9456-53b127fc289a	https://github.com/kovidgoyal/kitty/releases/tag/v0.49.0
	4daa8cea-433a-44bd-9456-53b127fc289a	https://secur0.com/en/cna/cve-list/cve-2026-95834-kitty-dnd-use-after-free

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "kitty",
          "programFiles": [
            "kitty/dnd.c"
          ],
          "repo": "https://github.com/kovidgoyal/kitty",
          "vendor": "Kovid Goyal",
          "versions": [
            {
              "lessThan": "0.49.0",
              "status": "affected",
              "version": "0.47.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "4daa8cea-433a-44bd-9456-53b127fc289a"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Use After Free in the drag source path of the drag and drop protocol in kitty from 0.47.0 before 0.49.0 allows a program writing to the terminal to cause the terminal to read from and write to freed heap memory, because drag_remote_file_data() in kitty/dnd.c holds a DragRemoteItem pointer into an array it does not own, calls toplevel_data_for_drag() or subdir_data_for_drag(), and then continues to use that pointer. Those helpers, and add_payload() and populate_dir_entries() which they call, report errors through the abrt() macro, which expands to cancel_drag() followed by a plain return, and cancel_drag() calls drag_free_offer(), which frees the array the pointer refers to. The helpers return void, so the caller receives no indication that the teardown happened, and proceeds to call all_children_complete() on the freed pointer, which dereferences it, and then to write through it. That dereference is guarded by a local flag that is set when the request carries no payload and announces no further data, which is the same condition that selects the finalisation block of add_payload(), so the error paths in that block reach it: a create that fails because an entry of the same name already exists, because the client may declare two entries with one name and the create operations use O_CREAT with O_EXCL and symlinkat(), a mkdirat() failure other than EEXIST, and the directory entry allocation paths. Both branches reach it. In the top level branch the caller\u0027s pointer is never cleared, so clearing the owning structure\u0027s own pointers during teardown does not help. In the sub directory branch subdir_data_for_drag() sets the caller\u0027s pointer to NULL on entry and assigns it only after its own last error path, so its own aborts leave the caller with NULL and are stopped by a null check, but it then calls add_payload() with that pointer set, and an abort there leaves the caller holding a freed child node inside the item tree, which drag_free_offer() frees by recursion. This results in undefined behaviour in the terminal process, reachable from the byte stream of any program running in the window."
    }
  ],
  "id": "CVE-2026-95834",
  "lastModified": "2026-09-25T17:17:20.223",
  "metrics": {
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "LOCAL",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 4.6,
          "baseSeverity": "MEDIUM",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "ACTIVE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "LOW",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "LOW",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "4daa8cea-433a-44bd-9456-53b127fc289a",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-95834",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-25T16:59:17.317677Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-25T17:17:20.223",
  "references": [
    {
      "source": "4daa8cea-433a-44bd-9456-53b127fc289a",
      "url": "https://github.com/kovidgoyal/kitty/commit/b54bfbb4f85f992edca9b04f5c0c2612454eec23"
    },
    {
      "source": "4daa8cea-433a-44bd-9456-53b127fc289a",
      "url": "https://github.com/kovidgoyal/kitty/releases/tag/v0.49.0"
    },
    {
      "source": "4daa8cea-433a-44bd-9456-53b127fc289a",
      "url": "https://secur0.com/en/cna/cve-list/cve-2026-95834-kitty-dnd-use-after-free"
    }
  ],
  "sourceIdentifier": "4daa8cea-433a-44bd-9456-53b127fc289a",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "4daa8cea-433a-44bd-9456-53b127fc289a",
      "type": "Secondary"
    }
  ]
}

CVE-2026-95834 (GCVE-0-2026-95834)

Vulnerability from cvelistv5 – Published: 2026-09-25 16:28 – Updated: 2026-09-25 16:59 X_Open Source

Title

Use after free in the kitty drag and drop protocol when a drag source item is aborted mid-transfer

Summary

Severity

4.6 (Medium)


                        
                          CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-25 16:59 UTC

CWE

CWE-416 - Use After Free

Assigner

Secur0 INCIBE root

References

3 references

URL	Tags
https://github.com/kovidgoyal/kitty/commit/b54bfb…	patch
https://github.com/kovidgoyal/kitty/releases/tag/…	release-notes
https://secur0.com/en/cna/cve-list/cve-2026-95834…	third-party-advisorytechnical-description

Impacted products

1 product

Vendor	Product	Version
Kovid Goyal	kitty	Affected: 0.47.0 , < 0.49.0 (semver) cpe:2.3:a:kovidgoyal:kitty::::::::

Credits

Gabriel Machado Tavares Cristian Fernández Cornejo Xoán M. Otero Jorge Secur0 CNA Kovid Goyal

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-95834",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-25T16:59:17.317677Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-25T16:59:26.692Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "kitty",
          "programFiles": [
            "kitty/dnd.c"
          ],
          "repo": "https://github.com/kovidgoyal/kitty",
          "vendor": "Kovid Goyal",
          "versions": [
            {
              "lessThan": "0.49.0",
              "status": "affected",
              "version": "0.47.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:kovidgoyal:kitty:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "0.49.0",
                  "versionStartIncluding": "0.47.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ],
          "operator": "OR"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Gabriel Machado Tavares"
        },
        {
          "lang": "en",
          "type": "analyst",
          "value": "Cristian Fern\u00e1ndez Cornejo"
        },
        {
          "lang": "en",
          "type": "analyst",
          "value": "Xo\u00e1n M. Otero Jorge"
        },
        {
          "lang": "en",
          "type": "coordinator",
          "value": "Secur0 CNA"
        },
        {
          "lang": "en",
          "type": "remediation developer",
          "value": "Kovid Goyal"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Use After Free in the drag source path of the drag and drop protocol in kitty from 0.47.0 before 0.49.0 allows a program writing to the terminal to cause the terminal to read from and write to freed heap memory, because \u003ccode\u003edrag_remote_file_data()\u003c/code\u003e in \u003ccode\u003ekitty/dnd.c\u003c/code\u003e holds a \u003ccode\u003eDragRemoteItem\u003c/code\u003e pointer into an array it does not own, calls \u003ccode\u003etoplevel_data_for_drag()\u003c/code\u003e or \u003ccode\u003esubdir_data_for_drag()\u003c/code\u003e, and then continues to use that pointer. Those helpers, and \u003ccode\u003eadd_payload()\u003c/code\u003e and \u003ccode\u003epopulate_dir_entries()\u003c/code\u003e which they call, report errors through the \u003ccode\u003eabrt()\u003c/code\u003e macro, which expands to \u003ccode\u003ecancel_drag()\u003c/code\u003e followed by a plain return, and \u003ccode\u003ecancel_drag()\u003c/code\u003e calls \u003ccode\u003edrag_free_offer()\u003c/code\u003e, which frees the array the pointer refers to. The helpers return \u003ccode\u003evoid\u003c/code\u003e, so the caller receives no indication that the teardown happened, and proceeds to call \u003ccode\u003eall_children_complete()\u003c/code\u003e on the freed pointer, which dereferences it, and then to write through it. That dereference is guarded by a local flag that is set when the request carries no payload and announces no further data, which is the same condition that selects the finalisation block of \u003ccode\u003eadd_payload()\u003c/code\u003e, so the error paths in that block reach it: a create that fails because an entry of the same name already exists, because the client may declare two entries with one name and the create operations use \u003ccode\u003eO_CREAT\u003c/code\u003e with \u003ccode\u003eO_EXCL\u003c/code\u003e and \u003ccode\u003esymlinkat()\u003c/code\u003e, a \u003ccode\u003emkdirat()\u003c/code\u003e failure other than \u003ccode\u003eEEXIST\u003c/code\u003e, and the directory entry allocation paths. Both branches reach it. In the top level branch the caller\u0027s pointer is never cleared, so clearing the owning structure\u0027s own pointers during teardown does not help. In the sub directory branch \u003ccode\u003esubdir_data_for_drag()\u003c/code\u003e sets the caller\u0027s pointer to \u003ccode\u003eNULL\u003c/code\u003e on entry and assigns it only after its own last error path, so its own aborts leave the caller with \u003ccode\u003eNULL\u003c/code\u003e and are stopped by a null check, but it then calls \u003ccode\u003eadd_payload()\u003c/code\u003e with that pointer set, and an abort there leaves the caller holding a freed child node inside the item tree, which \u003ccode\u003edrag_free_offer()\u003c/code\u003e frees by recursion. This results in undefined behaviour in the terminal process, reachable from the byte stream of any program running in the window."
            }
          ],
          "value": "Use After Free in the drag source path of the drag and drop protocol in kitty from 0.47.0 before 0.49.0 allows a program writing to the terminal to cause the terminal to read from and write to freed heap memory, because drag_remote_file_data() in kitty/dnd.c holds a DragRemoteItem pointer into an array it does not own, calls toplevel_data_for_drag() or subdir_data_for_drag(), and then continues to use that pointer. Those helpers, and add_payload() and populate_dir_entries() which they call, report errors through the abrt() macro, which expands to cancel_drag() followed by a plain return, and cancel_drag() calls drag_free_offer(), which frees the array the pointer refers to. The helpers return void, so the caller receives no indication that the teardown happened, and proceeds to call all_children_complete() on the freed pointer, which dereferences it, and then to write through it. That dereference is guarded by a local flag that is set when the request carries no payload and announces no further data, which is the same condition that selects the finalisation block of add_payload(), so the error paths in that block reach it: a create that fails because an entry of the same name already exists, because the client may declare two entries with one name and the create operations use O_CREAT with O_EXCL and symlinkat(), a mkdirat() failure other than EEXIST, and the directory entry allocation paths. Both branches reach it. In the top level branch the caller\u0027s pointer is never cleared, so clearing the owning structure\u0027s own pointers during teardown does not help. In the sub directory branch subdir_data_for_drag() sets the caller\u0027s pointer to NULL on entry and assigns it only after its own last error path, so its own aborts leave the caller with NULL and are stopped by a null check, but it then calls add_payload() with that pointer set, and an abort there leaves the caller holding a freed child node inside the item tree, which drag_free_offer() frees by recursion. This results in undefined behaviour in the terminal process, reachable from the byte stream of any program running in the window."
        }
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      "metrics": [
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            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "ACTIVE",
            "valueDensity": "NOT_DEFINED",
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          "url": "https://secur0.com/en/cna/cve-list/cve-2026-95834-kitty-dnd-use-after-free"
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    "datePublished": "2026-09-25T16:28:09.295Z",
    "dateReserved": "2026-09-22T16:30:20.014Z",
    "dateUpdated": "2026-09-25T16:59:26.692Z",
    "state": "PUBLISHED"
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}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

FKIE_CVE-2026-95834

CVE-2026-95834 (GCVE-0-2026-95834)

Tags

Sightings

Nomenclature

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