CVE-2025-55195
CVE-2025-55195 is a high-severity vulnerability with a CVSS 3.x base score of 7.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-1321.
Key facts
- Severity: High (CVSS 3.x base score 7.3)
- EPSS exploit prediction: 0% (23rd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2025-24881
- Weakness: CWE-1321
- Published:
- Last modified:
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.
Frequently asked questions
- What is CVE-2025-55195?
- @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.
- How severe is CVE-2025-55195?
- CVE-2025-55195 has a CVSS 3.x base score of 7.3, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
- Is CVE-2025-55195 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2025-55195?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2025-55195 have an EU (EUVD) identifier?
- Yes. CVE-2025-55195 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-24881.
- When was CVE-2025-55195 published?
- CVE-2025-55195 was published on 2025-08-14 and last updated on 2026-06-17.
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
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