Missing ownership check on the shared memory object named by the kitty askpass escape code
Summary
| CVE | CVE-2026-95835 |
|---|---|
| State | PUBLISHED |
| Assigner | Secur0 |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-25 17:17:20 UTC |
| Updated | 2026-09-25 18:17:33 UTC |
| Description | Missing Authorization in the askpass escape code handler in kitty from 0.25.0 before 0.49.0 allows a local user other than the one running the terminal to obtain the text typed into a prompt that kitty itself displays, because handle_remote_askpass() in kitty/window.py opens the POSIX shared memory object named in the escape code, parses a prompt definition out of it, and writes the user's answer back into an object of that same name, without at any point checking that the object is owned by the user running kitty or that its permissions exclude other users. The equivalent consumer of the same SharedMemory class in the ssh kitten performs exactly that check; the askpass path did not. The handler is reached through a device control string processed from the byte stream of the window, so the attacker must also cause bytes of their choosing to be displayed by the victim's terminal. Where the POSIX shared memory namespace is shared between the two users, a second local user can create an object with permissions that allow the victim to read and write it, cause the victim's kitty to render a prompt of the attacker's choosing, including a masked password prompt, and read the typed secret back out of the object afterwards. The prompt text is additionally passed to the display without control character sanitisation, so it can overwrite the warning line kitty prints above it. The answer is written by reopening an object of that name when the user answers, rather than through the handle already held. This results in disclosure of a secret typed by the victim to a second local user, and does not require any privilege on the victim's account. |
Risk And Classification
Primary CVSS: v4.0 5.6 MEDIUM from 4daa8cea-433a-44bd-9456-53b127fc289a
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:L/VA:N/SC:H/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: 0.001000000 probability, percentile 0.007850000 (date 2026-09-27)
Problem Types: CWE-862 | CWE-862 CWE-862 Missing Authorization
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | 4daa8cea-433a-44bd-9456-53b127fc289a | Secondary | 5.6 | MEDIUM | CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:L/VA:N/SC:H/SI:N/SA:N/E:X/C... |
| 4.0 | CNA | CVSS | 5.6 | MEDIUM | CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:L/VA:N/SC:H/SI:N/SA:N |
CVSS v4.0 Breakdown
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:H/VI:L/VA:N/SC:H/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
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Kovid Goyal | Kitty | affected 0.25.0 0.49.0 semver | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| secur0.com/en/cna/cve-list/cve-2026-95835-kitty-askpass-shared-memory-ow... | 4daa8cea-433a-44bd-9456-53b127fc289a | secur0.com | |
| github.com/kovidgoyal/kitty/releases/tag/v0.49.0 | 4daa8cea-433a-44bd-9456-53b127fc289a | github.com | |
| github.com/kovidgoyal/kitty/commit/3281919056c442e4ba6f5abed7ee2c5130de31ff | 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. Only systems on which the two users share a POSIX shared memory namespace are exposed to the cross-user case; a session confined to its own mount namespace with its own /dev/shm, as in a container, is not.