CVE-2026-48697
CVE-2026-48697 is a high-severity vulnerability in Pavel-odintsov Fastnetmon with a CVSS 3.x base score of 7.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-295.
Key facts
- Severity: High (CVSS 3.x base score 7.4)
- EPSS exploit prediction: 0% (6th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-31900
- Weakness: CWE-295
- Affected product: Pavel-odintsov Fastnetmon
- Published:
- Last modified:
Description
FastNetMon Community Edition through 1.2.9 does not verify TLS certificates on outbound HTTPS connections. The execute_web_request_secure() function in src/fast_library.cpp creates a boost::asio::ssl::context with tls_client mode and calls set_default_verify_paths() to load CA certificates, but never calls set_verify_mode(boost::asio::ssl::verify_peer). Without this call, OpenSSL performs the TLS handshake without validating the server's certificate chain, making all HTTPS connections vulnerable to man-in-the-middle attacks. This function is used for telemetry reporting to community-stats.fastnetmon.com, which sends system information including CPU model, kernel version, traffic statistics, and software configuration. An attacker can intercept and modify this data or redirect it to a malicious server.
Frequently asked questions
- What is CVE-2026-48697?
- FastNetMon Community Edition through 1.2.9 does not verify TLS certificates on outbound HTTPS connections. The execute_web_request_secure() function in src/fast_library.cpp creates a boost::asio::ssl::context with tls_client mode and calls set_default_verify_paths() to load CA certificates, but never calls set_verify_mode(boost::asio::ssl::verify_peer). Without this call, OpenSSL performs the TLS handshake without validating the server's certificate chain, making all HTTPS connections vulnerable to man-in-the-middle attacks. This function is used for telemetry reporting to community-stats.fastnetmon.com, which sends system information including CPU model, kernel version, traffic statistics, and software configuration. An attacker can intercept and modify this data or redirect it to a malicious server.
- How severe is CVE-2026-48697?
- CVE-2026-48697 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability none.
- Is CVE-2026-48697 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-48697?
- CVE-2026-48697 affects Pavel-odintsov Fastnetmon. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2026-48697?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2026-48697 have an EU (EUVD) identifier?
- Yes. CVE-2026-48697 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31900.
- When was CVE-2026-48697 published?
- CVE-2026-48697 was published on 2026-05-26 and last updated on 2026-06-17.
References
- https://github.com/pavel-odintsov/fastnetmon
- https://github.com/pavel-odintsov/fastnetmon/blob/master/src/fast_library.cpp
- https://lorikeetsecurity.com/blog/fastnetmon-cve-2026-48697-missing-tls-validation
Affected products (1)
- cpe:2.3:a:pavel-odintsov:fastnetmon:*:*:*:*:community:*:*:*
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