CVE-2025-55195
@std/toml Prototype Pollution in Node.js and Browser
@std/toml is the Deno Standard Library. Prior to version 1.0.9, an attacker can pollute the prototype chain in Node.js runtime and Browser when parsing untrusted TOML data, thus achieving Prototype Pollution (PP) vulnerability. This is because the library is merging an untrusted object with an empty object, which by default the empty object has the prototype chain. This issue has been patched in version 1.0.9.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
7.3
@std/toml Prototype Pollution in Node.js and Browser
@std/toml is the Deno Standard Library. Prior to version 1.0.9, an attacker can pollute the prototype chain in Node.js runtime and Browser when parsing untrusted TOML data, thus achieving Prototype Pollution (PP) vulnerability. This is because the library is merging an untrusted object with an empty object, which by default the empty object has the prototype chain. This issue has been patched in version 1.0.9.
- Record
CVE-2025-55195- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-1321
- Updated
- 2026-11-02
EUVDEUVD-2025-24881
7.3
@std/toml is the Deno Standard Library. Prior to version 1.0.9, an attacker can pollute the prototype chain in Node.js runtime and Browser when parsing untrusted TOML data, thus achieving Prototype Pollution (PP) vulnerability. This is because the library is merging an untrusted object with an empty object, which by default the empty object has the prototype chain. This issue has been patched in version 1.0.9.
- Record
EUVD-2025-24881- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Updated
- 2026-11-02
NVD
7.3
@std/toml is the Deno Standard Library. Prior to version 1.0.9, an attacker can pollute the prototype chain in Node.js runtime and Browser when parsing untrusted TOML data, thus achieving Prototype Pollution (PP) vulnerability. This is because the library is merging an untrusted object with an empty object, which by default the empty object has the prototype chain. This issue has been patched in version 1.0.9.
- Record
CVE-2025-55195- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-1321
- Updated
- 2026-11-02
OSV
7.3
@std/toml Prototype Pollution in Node.js and Browser
@std/toml is the Deno Standard Library. Prior to version 1.0.9, an attacker can pollute the prototype chain in Node.js runtime and Browser when parsing untrusted TOML data, thus achieving Prototype Pollution (PP) vulnerability. This is because the library is merging an untrusted object with an empty object, which by default the empty object has the prototype chain. This issue has been patched in version 1.0.9.
- Record
CVE-2025-55195- CVSS 3.1
- 7.3 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-1321
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-55195 is a high vulnerability (CVSS 7.3) in Denoland Std, published August 14, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.36%, the 30th percentile. No source names a fixed version.
References
github.com/denoland/std/security/advisories/GHSA-crjp-8r9q-2j9r
github.com/denoland/std/commit/540662cfd6d71e969af292aa604ef4049dbe271b
github.com/denoland/std/releases/tag/release-2025.08.13
github.com/CVEProject/cvelistV5/tree/main/cves/2025/55xxx/CVE-2025-55195.json
nvd.nist.gov/vuln/detail/CVE-2025-55195