CVE-2019-15547
HIGHCVE-2019-15547 is a high-severity (CVSS 7.5) CWE-134 vulnerability in ncurses_project ncurses. O3 Security detects and blocks CVE-2019-15547 exploitation at runtime via eBPF exploit-chain detection and L7 egress monitoring, even on unpatched systems.
An issue was discovered in the ncurses crate through 5.99.0 for Rust. There are format string issues in printw functions because C format arguments are mishandled.
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-2019-15547 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 364,277 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Description
An issue was discovered in the ncurses crate through 5.99.0 for Rust. There are format string issues in printw functions because C format arguments are mishandled.
Affected Products
ncursesncurses_projectDetection & mitigation playbook
Vendor / applianceDetect
Inventory every ncurses_project ncurses deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.
Remediation status
No patch has shipped for CVE-2019-15547 yet — track the ncurses_project ncurses advisory for a fixed release and apply the workarounds below in the meantime.
Mitigate without a patch
Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.
How O3 protects you
O3 detects and blocks CVE-2019-15547 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.
Tailored to CVE-2019-15547. 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-2019-15547 being exploited in your environment?
O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2019-15547 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.