CVE-2026-12522
Out-of-bounds WriteThe HL7800 cellular modem driver's +CGCONTRDP: response handler on_cmd_atcmdinfo_ipaddr() in drivers/modem/vendor_standalone/hl7800.c parses the PDP-context dynamic parameters (local address, subnet mask, gateway, and DNS servers) that the cellular network assigns to the device. The response is linearized into a 256-byte stack buffer, after which each address field length is computed from comma/. delimiter positions in the network-supplied data and used directly as the length argument to strncpy() into the fixed 64-byte stack buffer temp_addr_str (and the 16-byte iface_ctx.dns_v4_string).
Because the field length is derived from attacker-controlled delimiter positions and was not bounded against the destination buffer, a single field can be far larger than 64 bytes. A malicious or impersonated cellular network (for example a rogue base station) can return a crafted +CGCONTRDP response with an overlong address field, causing strncpy() to write past temp_addr_str on the modem worker thread's stack, plus an out-of-bounds NUL write at temp_addr_str[addr_len].
No device-side privileges or user interaction are required: the device itself issues the AT+CGCONTRDP=1 query during normal network attach and parses whatever the network returns. The overflow corrupts adjacent stack memory in supervisor context, yielding at minimum a remotely triggerable crash and potentially control-flow hijacking on targets without stack protection.
The fix bounds every field length against its destination buffer (temp_addr_str and dns_v4_string) before each copy, rejecting overlong fields.
Deep Security Visibility Without the Complexity
SynScan provides clear, real-time security insights so you can monitor your attack surface, spot risks early, and act fast—without extra complexity.
- No setup fees
- 5-min deployment
- Cancel anytime
Frequently Asked Questions
A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.
Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.
Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.
SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.