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

MITRE NVD CVE.ORG JSON API

Summary

CVECVE-2026-95834
StatePUBLISHED
AssignerSecur0
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-09-25 17:17:20 UTC
Updated2026-09-25 17:17:20 UTC
DescriptionUse 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.

Risk And Classification

Primary CVSS: v4.0 4.6 MEDIUM from 4daa8cea-433a-44bd-9456-53b127fc289a

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

EPSS: 0.001270000 probability, percentile 0.019890000 (date 2026-09-27)

Problem Types: CWE-416 | CWE-416 CWE-416 Use After Free

VersionSourceTypeScoreSeverityVector
4.04daa8cea-433a-44bd-9456-53b127fc289aSecondary4.6MEDIUMCVSS: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/C...
4.0CNACVSS4.6MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N

CVSS v4.0 Breakdown

Attack Vector
Local
Attack Complexity
Low
Attack Requirements
None
Privileges Required
None
User Interaction
Active
Confidentiality
None
Integrity
Low
Availability
Low
Sub Conf.
None
Sub Integrity
None
Sub Availability
None

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

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Kovid Goyal Kitty affected 0.47.0 0.49.0 semver Not specified

References

ReferenceSourceLinkTags
github.com/kovidgoyal/kitty/commit/b54bfbb4f85f992edca9b04f5c0c2612454eec23 4daa8cea-433a-44bd-9456-53b127fc289a github.com
secur0.com/en/cna/cve-list/cve-2026-95834-kitty-dnd-use-after-free 4daa8cea-433a-44bd-9456-53b127fc289a secur0.com
github.com/kovidgoyal/kitty/releases/tag/v0.49.0 4daa8cea-433a-44bd-9456-53b127fc289a github.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

CNA: Gabriel Machado Tavares (en)

CNA: Cristian Fernández Cornejo (en)

CNA: Xoán M. Otero Jorge (en)

CNA: Secur0 CNA (en)

CNA: Kovid Goyal (en)

Additional Advisory Data

Solutions

CNA: Upgrade to kitty 0.49.0 or later.

© CVE.report 2026

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report