CVE-2025-48888 — deno
Fix: denoland/deno@2f0fae9CVE-2025-48888 is a CWE-863 vulnerability in deno. A fix is available for deno — see the affected versions and patch details below.
Deno run with --allow-read and --deny-read flags results in allowed
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.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-48888.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
deno🦀deno🦀deno🦀deno_runtimeReal-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
Deno is a JavaScript, TypeScript, and WebAssembly runtime. Starting in version 1.41.3 and prior to versions 2.1.13, 2.2.13, and 2.3.2, deno run --allow-read --deny-read main.ts results in allowed, even though 'deny' should be stronger. The result is the same with all global unary permissions given as --allow-* --deny-*. This only affects a nonsensical combination of flags, so there shouldn't be a real impact on the userbase. Users may upgrade to version 2.1.13, 2.2.13, or 2.3.2 to receive a patch.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | deno | ≥ 1.41.3&&< 2.1.13 | 2.1.13cargo update -p deno --precise 2.1.13 |
| 🦀crates.io | deno | ≥ 2.2.0&&< 2.2.13 | 2.2.13cargo update -p deno --precise 2.2.13 |
| 🦀crates.io | deno | ≥ 2.3.0&&< 2.3.2 | 2.3.2cargo update -p deno --precise 2.3.2 |
| 🦀crates.io | deno_runtime | ≥ 0.150.0&&< 0.212.0 | 0.212.0cargo update -p deno_runtime --precise 0.212.0 |
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 2.1.13 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-48888 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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-48888 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2025-48888. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-48888 in your dependencies?
O3 Security finds CVE-2025-48888 across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.