CVE-2026-49206
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AI Threat Summary
CVE-2026-49206 is a moderate vulnerability with a CVSS score of 2.9 affecting the target software. Threat hunters should monitor for exploit attempts and apply vendor patches immediately.
Description
rapidcsv is a C++ CSV parser library. Prior to 8.99, RemoveColumn, InsertColumn, RemoveRow, InsertRow, and GetColumnNames converted size_t indexes to int before adding them to std::vector iterators. On 64-bit systems, in a CSV matrix dimension containing more than 2^31 elements, an index above INT_MAX could wrap to a negative iterator offset and point before the start of the vector, causing undefined behavior, heap memory corruption, or a crash. Triggering the issue requires an extremely large in-memory document, requiring tens of gigabytes of memory at minimum, so typical CSV documents are not practically affected. This issue is fixed in version 8.99.
Attack Chain
Attacker identifies vulnerable service instances using Shodan, Censys, or active scanning
Attacker crafts malicious payload exploiting CVE-2026-49206 to achieve remote code execution
Attacker executes arbitrary OS commands or shellcode in the context of the vulnerable process
Attacker installs backdoor, cron job, or web shell for persistent access
Attacker uses compromised host as pivot point to access internal network resources
MITRE ATT&CK Techniques
Attacker exploits the vulnerability in an internet-facing service to gain initial access
Post-exploitation shell commands executed through the vulnerability
Attacker downloads malware or tools after gaining code execution
Indicators of Compromise
| Type | Value | Description | |
|---|---|---|---|
| user_agent | Mozilla/5.0 (compatible; exploit/1.0) |
Generic exploit scanner user agent pattern | |
| url | /api/vuln-endpoint?payload=<malicious> |
Exploit attempt against application endpoint — monitor access logs for anomalous params |
Remediation
Quick Facts
| CVE ID | CVE-2026-49206 |
| CVSS Score | 2.9 |
| Vector | CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L |
| Published | 2026-10-14 |
| Exploited | No |
| CISA KEV | No |
| PoC | Not public |