CVE-2026-55487: pnpm: manifest identity spoof satisfies allowBuilds and runs attacker lifecycle

Severity: high (CVSS 8.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-06-25 · updated 2026-06-29
Weakness: CWE-346

Description

pnpm is a package manager. Prior to 10.34.2 and 11.5.3, the generic peer-suffix normalizer also stripped parenthesized text from git, URL, tarball, file, and other opaque locators. Approval for one source string could therefore authorize a different attacker-controlled source whose locator normalized to the same value. This vulnerability is fixed in 10.34.2 and 11.5.3.

Affected products

pnpm: before 10.34.2; from 11.0.0 before 11.5.3 — fixed in 10.34.2, 11.5.3

How to fix

Upgrade to a fixed version: pnpm 10.34.2, 11.5.3. Check the vendor advisory for mitigations.

References

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