CVE-2026-40931
Physical" divergence, an attacker can bypass the security check using a Directory Poisoning technique (pre-existing symbolic links).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.26%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Compressing is a compressing and uncompressing lib for node. Prior to 2.1.1 and 1.10.5, the patch for CVE-2026-24884 relies on a purely logical string validation within the isPathWithinParent utility. This check verifies if a resolved path string starts with the destination directory string but fails to account for the actual filesystem state. By exploiting this "Logical vs. Physical" divergence, an attacker can bypass the security check using a Directory Poisoning technique (pre-existing symbolic links). This vulnerability is fixed in 2.1.1 and 1.10.5.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.26% probability · 18th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-59
- Affected
- node-modules/compressing
- Source
- security-advisories@github.com
References
- https://github.com/node-modules/compressing/security/advisories/GHSA-4c3q-x735-j3r5Exploit, Mitigation, Vendor Advisory
- https://github.com/node-modules/compressing/security/advisories/GHSA-4c3q-x735-j3r5Exploit, Mitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.