What’s Vulnerable › Vulnerabilities

CVE-2025-55195: @std/toml Prototype Pollution in Node.js and Browser

• Severity: high (CVSS 7.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2025-08-14 · updated 2026-06-17
• Weakness: CWE-1321

Description

@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.

Affected products

• denoland std: before 1.0.9

References

• https://github.com/denoland/std/commit/540662cfd6d71e969af292aa604ef4049dbe271b
• https://github.com/denoland/std/releases/tag/release-2025.08.13
• https://github.com/denoland/std/security/advisories/GHSA-crjp-8r9q-2j9r
• https://github.com/denoland/std/security/advisories/GHSA-crjp-8r9q-2j9r

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