projen: Relative Path Traversal
CVE-2026-89065 is a high-severity relative path traversal vulnerability in projen from AWS, with a CVSS 3.1 base score of 7.1 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 0.101.37 as the first without the flaw, so updating projen to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.18% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update projen to 0.101.37 or a later version.
- Read the advisory on aws.amazon.com for workarounds and exact fixed builds.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H. Scored by CNA.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 6.8 | Medium | CNA |
| CVSS 3.1 | 7.1 | High | CNA |
Official description
Relative path traversal in the generated file manifest cleanup component in projen before 0.101.37 might allow context-dependent attackers to recursively delete files and directories outside the project directory that are writable by the environment running projen, via crafted entries in the version-controlled generated file manifest that is consumed during project synthesis. To remediate this issue, users should upgrade to version 0.101.37. The corrected containment check is automatically applied by the projen runtime next time you run it.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Relative Path Traversal
The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as.. that can resolve to a location that is outside of that directory.
How developers prevent this class of flaw
- Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
References
Advisories
Patches and release notes
Other vulnerabilities in projen
- 7.8 High severity
Recent Relative Path Traversal vulnerabilities
- 9.1 Critical severity
- 7.7 High severity
- 8.6 High severity
- 8.8 High severity
- 8.1 High severity
- 7.4 High severity
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