CVE-2024-27936
Deno interactive permission prompt spoofing via improper ANSI stripping
Deno is a JavaScript, TypeScript, and WebAssembly runtime with secure defaults. Starting in version 1.32.1 and prior to version 1.41.0 of the deno library, maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents. Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences. Any Deno program can spoof the content of the interactive permission prompt by inserting a broken ANSI code, which allows a malicious Deno program to display the wrong file path or program name to the user. Version 1.41.0 of the deno library contains a patch for the issue.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Required
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
8.8
Deno interactive permission prompt spoofing via improper ANSI stripping
Deno is a JavaScript, TypeScript, and WebAssembly runtime with secure defaults. Starting in version 1.32.1 and prior to version 1.41.0 of the deno library, maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents. Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences. Any Deno program can spoof the content of the interactive permission prompt by inserting a broken ANSI code, which allows a malicious Deno program to display the wrong file path or program name to the user. Version 1.41.0 of the deno library contains a patch for the issue.
- Record
CVE-2024-27936- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-150
- Updated
- 2026-11-02
EUVDEUVD-2024-0957
8.8
Deno is a JavaScript, TypeScript, and WebAssembly runtime with secure defaults. Starting in version 1.32.1 and prior to version 1.41.0 of the deno library, maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents. Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences. Any Deno program can spoof the content of the interactive permission prompt by inserting a broken ANSI code, which allows a malicious Deno program to display the wrong file path or program name to the user. Version 1.41.0 of the deno library contains a patch for the issue.
- Record
EUVD-2024-0957- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-m4pq-fv2w-6hrw
8.8
Deno's deno_runtime vulnerable to interactive permission prompt spoofing via improper ANSI stripping
Summary
A maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents.
Details
In the patch for CVE-2023-28446, Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences.
For example, requesting the read permission with /tmp/hello\u001b[/../../etc/hosts as a path will display the /tmp/hellotc/hosts in the permission prompt, but the actual permission given to the program is /tmp/hello\u001b[/../../etc/hosts, which is /etc/hosts after the normalization.
This difference allows a malicious Deno program to spoof the contents of the permission prompt.
PoC
Run the following JavaScript and observe that /tmp/hellotc/hosts is displayed in the permission prompt instead of /etc/hosts, although Deno gives access to /etc/hosts.
const permission = { name: "read", path: "/tmp/hello\u001b[/../../etc/hosts" };
await Deno.permissions.request(permission);
console.log(await Deno.readTextFile("/etc/hosts"));
Expected prompt
┌ ⚠️ Deno requests read access to "/etc/hosts".
├ Requested by `Deno.permissions.query()` API
├ Run again with --allow-read to bypass this prompt.
└ Allow? [y/n/A] (y = yes, allow; n = no, deny; A = allow all read permissions) >
Actual prompt
┌ ⚠️ Deno requests read access to "/tmp/hellotc/hosts".
├ Requested by `Deno.permissions.query()` API
├ Run again with --allow-read to bypass this prompt.
└ Allow? [y/n/A] (y = yes, allow; n = no, deny; A = allow all read permissions) >
Impact
Any Deno program can spoof the content of the interactive permission prompt by inserting a broken ANSI code, which allows a malicious Deno program to display the wrong file path or program name to the user.
- Record
GHSA-m4pq-fv2w-6hrw- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-150
- Updated
- 2026-11-02
NVD
8.8
Deno is a JavaScript, TypeScript, and WebAssembly runtime with secure defaults. Starting in version 1.32.1 and prior to version 1.41.0 of the deno library, maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents. Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences. Any Deno program can spoof the content of the interactive permission prompt by inserting a broken ANSI code, which allows a malicious Deno program to display the wrong file path or program name to the user. Version 1.41.0 of the deno library contains a patch for the issue.
- Record
CVE-2024-27936- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - Weakness
- CWE-150
- Updated
- 2026-11-02
OSV
8.8
Deno interactive permission prompt spoofing via improper ANSI stripping
Deno is a JavaScript, TypeScript, and WebAssembly runtime with secure defaults. Starting in version 1.32.1 and prior to version 1.41.0 of the deno library, maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents. Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences. Any Deno program can spoof the content of the interactive permission prompt by inserting a broken ANSI code, which allows a malicious Deno program to display the wrong file path or program name to the user. Version 1.41.0 of the deno library contains a patch for the issue.
- Record
CVE-2024-27936- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-150
- Updated
- 2026-11-02
OSVGHSA-m4pq-fv2w-6hrw
8.8
Deno's deno_runtime vulnerable to interactive permission prompt spoofing via improper ANSI stripping
Summary
A maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents.
Details
In the patch for CVE-2023-28446, Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences.
For example, requesting the read permission with /tmp/hello\u001b[/../../etc/hosts as a path will display the /tmp/hellotc/hosts in the permission prompt, but the actual permission given to the program is /tmp/hello\u001b[/../../etc/hosts, which is /etc/hosts after the normalization.
This difference allows a malicious Deno program to spoof the contents of the permission prompt.
PoC
Run the following JavaScript and observe that /tmp/hellotc/hosts is displayed in the permission prompt instead of /etc/hosts, although Deno gives access to /etc/hosts.
const permission = { name: "read", path: "/tmp/hello\u001b[/../../etc/hosts" };
await Deno.permissions.request(permission);
console.log(await Deno.readTextFile("/etc/hosts"));
Expected prompt
┌ ⚠️ Deno requests read access to "/etc/hosts".
├ Requested by `Deno.permissions.query()` API
├ Run again with --allow-read to bypass this prompt.
└ Allow? [y/n/A] (y = yes, allow; n = no, deny; A = allow all read permissions) >
Actual prompt
┌ ⚠️ Deno requests read access to "/tmp/hellotc/hosts".
├ Requested by `Deno.permissions.query()` API
├ Run again with --allow-read to bypass this prompt.
└ Allow? [y/n/A] (y = yes, allow; n = no, deny; A = allow all read permissions) >
Impact
Any Deno program can spoof the content of the interactive permission prompt by inserting a broken ANSI code, which allows a malicious Deno program to display the wrong file path or program name to the user.
- Record
GHSA-m4pq-fv2w-6hrw- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-150
- Updated
- 2026-11-02
OSVJLSEC-2026-105
6.5
Deno's `deno_runtime` vulnerable to interactive permission prompt spoofing via improper ANSI stripping
Summary
A maliciously crafted permission request can show the spoofed permission prompt by inserting a broken ANSI escape sequence into the request contents.
Details
In the patch for CVE-2023-28446, Deno is stripping any ANSI escape sequences from the permission prompt, but permissions given to the program are based on the contents that contain the ANSI escape sequences.
For example, requesting the read permission with /tmp/hello\u001b[/../../etc/hosts as a path will display the /tmp/hellotc/hosts in the permission prompt, but the actual permission given to the program is /tmp/hello\u001b[/../../etc/hosts, which is /etc/hosts after the normalization.
This difference allows a malicious Deno program to spoof the contents of the permission prompt.
PoC
Run the following JavaScript and observe that /tmp/hellotc/hosts is displayed in the permission prompt instead of /etc/hosts, although Deno gives access to /etc/hosts.
const permission = { name: "read", path: "/tmp/hello\u001b[/../../etc/hosts" };
await Deno.permissions.request(permission);
console.log(await Deno.readTextFile("/etc/hosts"));
Expected prompt
┌ ⚠️ Deno requests read access to "/etc/hosts".
├ Requested by `Deno.permissions.query()` API
├ Run again with --allow-read to bypass this prompt.
└ Allow? [y/n/A] (y = yes, allow; n = no, deny; A = allow all read permissions) >
Actual prompt
┌ ⚠️ Deno requests read access to "/tmp/hellotc/hosts".
├ Requested by `Deno.permissions.query()` API
├ Run again with --allow-read to bypass this prompt.
└ Allow? [y/n/A] (y = yes, allow; n = no, deny; A = allow all read permissions) >
Impact
Any Deno program can spoof the content of the interactive permission prompt by inserting a broken ANSI code, which allows a malicious Deno program to display the wrong file path or program name to the user.
- Record
JLSEC-2026-105- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
denocrates.io |
1.32.1 up to 1.41.0 | 1.41.0 |
deno_runtimecrates.io |
0.103.0 up to 0.147.0 | 0.147.0 |
Deno_jllJulia |
1.33.4+0 up to 2.0.0+0 | 2.0.0+0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2024-27936 is a high vulnerability (CVSS 8.8) in Deno, published March 5, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.94%, the 61st percentile. Fixed in deno 1.41.0.
References
github.com/denoland/deno/security/advisories/GHSA-m4pq-fv2w-6hrw
github.com/denoland/deno/commit/78d430103a8f6931154ddbbe19d36f3b8630286d
github.com/denoland/deno/commit/7e6b94231290020b55f1d08fb03ea8132781abc5
nvd.nist.gov/vuln/detail/CVE-2024-27936
github.com/advisories/GHSA-m4pq-fv2w-6hrw
github.com/CVEProject/cvelistV5/tree/main/cves/2024/27xxx/CVE-2024-27936.json
github.com/denoland/deno