VulnerabilityPublished 13 Aug 2026Updated 26 Oct 2026

CVE-2026-55699: Reserved bin name deletes PNPM_HOME during global remove

Affects pnpm@10Source GCVE Database

Not known to be exploited · CVSS 6.5 Medium : upgrade to 10.34.2 when convenient.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

6.5Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.4% chance of exploitation in 30 days – higher than 38% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 10.34.2

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 13 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade pnpm@10 to 10.34.2.

Affected software

Product	Affected	Fixed in
Homebrewpnpm@10`pkg:brew/pnpm%4010`Other threats	Affected >=10.33.2 <10.34.2	Fixed in 10.34.2

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

Description

<details> <summary>Maintainer Action Plan</summary> ## Maintainer Action Plan This report is ready to review with the shared patch branch. Start with the PR and the expected fixed behavior, then use the detailed exploit narrative below only if you want to replay the original path. - Advisory: `CAND-PNPM-085` / `GHSA-4gxm-v5v7-fqc4` - Advisory URL: https://github.com/pnpm/pnpm/security/advisories/GHSA-4gxm-v5v7-fqc4 - Shared patch PR: https://github.com/pnpm/pnpm-ghsa-j2hc-m6cf-6jm8/pull/1 - Shared patch branch: `security/ghsa-batch-2026-06-09` - Patch commit: `a93449314f398cf4bdf2e28d033c02d37395ad22` - Base commit: `origin/main` `55a4035abf1ae3fe7208ba1f5ef43c5eff58ccec` - Maintainer priority: `appendix` - Component: `pnpm global add/remove bin cleanup` - Patch area: bin name/path segment validation - Affected packages: `npm:pnpm` - CWE IDs: `CWE-22`, `CWE-73` - Conservative CVSS: `6.5` / `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H` - Next action: review the shared patch branch for this component, set the final affected version range, merge and release the fix, then publish or close the advisory. ### Expected Patched Behavior Reserved, dot, and path-segment bin names are rejected or ignored; global remove leaves `PNPM_HOME` and the sentinel file intact. ### Files And Tests To Review - `bins/resolver/src/index.ts` - `bins/resolver/test/index.ts` - `global/commands/test/globalRemove.test.ts` - `pacquet/crates/cmd-shim/src/bin_resolver.rs` - `pacquet/crates/cmd-shim/src/bin_resolver/tests.rs` - `.changeset/strange-bin-segments.md` ### Focused Validation Run these from a checkout of the shared patch branch. They are the useful maintainer commands with machine-local artifact paths removed. - Use the private PR checks plus the patched replay coverage matrix for this candidate. The full patched replay for the shared branch passed with all 20 candidates marked fixed. This candidate's replay evidence is `results/CAND-PNPM-085-patched-result.json`.  ## Title Reserved manifest bin names can make global package operations delete outside the global bin directory </details> ## Description ### Summary Manifest `bin` object keys such as `""`, `"."`, and `".."` passed pnpm's bin-name guard. When a malicious package was installed globally, later global remove, update, or add-replacement flows could re-derive those names from the installed manifest and pass `path.join(globalBinDir, binName)` to `removeBin`. For `"."` this targets the global bin directory; for `".."` this targets its parent. ### Details The vulnerable dataflow was: - `bins/resolver/src/index.ts` converted manifest `bin` object keys to `binName` and only required URL-safe text or `$`. Empty, dot, dot-dot, and scoped forms such as `@scope/..` were not rejected after scope stripping. - `global/packages/src/scanGlobalPackages.ts` scanned installed global package manifests and returned manifest-derived `bin.name` values. - `global/commands/src/globalRemove.ts`, `global/commands/src/globalUpdate.ts`, and global add replacement logic joined those names to `globalBinDir`. - `bins/remover/src/removeBins.ts` recursively removed the resulting path. Install-time checks did not close the gap: bin target paths were package-root checked, conflict checks looked at the same escaped path but did not reject reserved segments, and bin-link warning paths could leave the package installed for later global operations. ### PoC Run: The script first performs a safe prepatch simulation in a temporary directory: ```text prepatch_reserved_bin_name=.. prepatch_delete_target=/.../cand-pnpm-085.XXXXXX/home prepatch_deleted_global_bin_parent=true ``` It then validates the patched implementation: ```bash ./node_modules/.bin/tsgo --build bins/resolver/tsconfig.json ./node_modules/.bin/tsgo --build global/commands/tsconfig.json ./node_modules/.bin/eslint bins/resolver/src/index.ts bins/resolver/test/index.ts global/commands/test/globalRemove.test.ts cd bins/resolver NODE_OPTIONS="--experimental-vm-modules --disable-warning=ExperimentalWarning --disable-warning=DEP0169" ../../node_modules/.bin/jest test/index.ts --runInBand cd global/commands NODE_OPTIONS="--experimental-vm-modules --disable-warning=ExperimentalWarning --disable-warning=DEP0169" ../../node_modules/.bin/jest test/globalRemove.test.ts -t "global remove ignores reserved manifest bin names" --runInBand cargo fmt --manifest-path pacquet/crates/cmd-shim/Cargo.toml --check cargo test --manifest-path pacquet/crates/cmd-shim/Cargo.toml bin_resolver --lib git diff --check -- bins/resolver global/commands/test/globalRemove.test.ts pacquet/crates/cmd-shim .changeset/strange-bin-segments.md pnpm-lock.yaml ``` The patched resolver no longer emits reserved bin names, and the global-remove regression proves the deletion sink receives only `path.join(globalBinDir, "good")`. ### Impact Direct confidentiality impact was not validated for this primitive; the sink is deletion/corruption,

References

Community reviews

Loading reviews…