CVE-2018-5158 — pdfjs-dist
HIGHCVE-2018-5158 is a high-severity (CVSS 8.8) Code Injection vulnerability in pdfjs-dist. EPSS puts its 30-day exploitation probability at 10.4% (96th percentile). A fix is available for pdfjs-dist — see the affected versions and patch details below.
Malicious PDF can inject JavaScript into PDF Viewer
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.
How urgent is this, really
CVE-2018-5158 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
pdfjs-distnpmDescription
The PDF viewer does not sufficiently sanitize PostScript calculator functions, allowing malicious JavaScript to be injected through a crafted PDF file. This JavaScript can then be run with the permissions of the PDF viewer by its worker. This vulnerability affects Firefox ESR < 52.8 and Firefox < 60.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | pdfjs-dist | ≥ 2.0.0&&< 2.0.550 | 2.0.550npm install pdfjs-dist@2.0.550 |
| 📦npm | pdfjs-dist | all versions | 1.10.100npm install pdfjs-dist@1.10.100 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pdfjs-dist, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update pdfjs-dist to 2.0.550 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-5158 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-2018-5158 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2018-5158. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 6 | firefox-0:52.8.0-1.el6_9 | RHSA-2018:1414 |
| Red Hat Enterprise Linux 7 | firefox-0:52.8.0-1.el7_5 | RHSA-2018:1415 |
Frequently Asked Questions
Is CVE-2018-5158 in your dependencies?
O3 Security finds CVE-2018-5158 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.