# CESNET vulnerabilities Source: https://junglewise.ai/threats/vendors/cesnet Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats Updated: 12 November 2026, 03:07 UTC. Rebuilt every hour. Data: https://junglewise.ai/threats/vendors/cesnet.json License: CC BY 4.0 with a link back Junglewise Threat Intelligence has tracked 7 vulnerabilities in CESNET: 0 in the last 7 days and 5 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2026-122130, was published on 4 November 2026. 5 vulnerabilities in the last four weeks, up from none in the four before. 2 technologies have a page of their own. ## Counts - Last 7 days: 0 - Last 30 days: 5 - Last 90 days: 5 - All time: 7 (0 critical, 0 exploited in the wild) ## About CESNET Czech academic and research network organization providing networking and IT services. ## Latest CESNET vulnerabilities - [CVE-2026-122130: CESNET ipfixcol2 integer overflow in Forwarder plugin](https://junglewise.ai/threats/cve-2026-122130-cesnet-ipfixcol2-2-3-0-before-2-9-0-contains-an-integer-overflow) (high, CVSS 8.2, published 4 Nov 2026) - [CVE-2026-122129: CESNET ipfixcol2 memory exhaustion in LZ4 decoder](https://junglewise.ai/threats/cve-2026-122129-cesnet-ipfixcol2-2-7-1-before-2-9-0-contains-a-memory-allocation) (medium, CVSS 5.3, published 4 Nov 2026) - [CVE-2026-122127: CESNET ipfixcol2 heap buffer overflow in LZ4 decompression](https://junglewise.ai/threats/cve-2026-122127-cesnet-ipfixcol2-2-7-1-before-2-9-0-contains-a-heap-based-buffer) (high, CVSS 7.5, published 4 Nov 2026) - [CVE-2026-63201: Netopeer2 format string vulnerability in RPC handling](https://junglewise.ai/threats/cve-2026-63201-netopeer2-is-a-server-for-implementing-network-configuration) (info, published 30 Oct 2026) - [CVE-2026-115327: libyang uninitialized pointer free in NETCONF RPC parsing](https://junglewise.ai/threats/cve-2026-115327-libyang-through-6-4-13-contains-an-uninitialized-pointer-free) (medium, CVSS 5.3, published 22 Oct 2026) - [CVE-2026-41401: CESNET libyang heap use-after-free in lyd_parser_set_data_flags](https://junglewise.ai/threats/cve-2026-41401-cesnet-libyang-heap-use-after-free-in-lyd-parser-set-data-flags) (medium, CVSS 6.5, published 26 May 2026) - [CVE-2026-44673: CESNET libyang heap buffer overflow in lyb_read_string](https://junglewise.ai/threats/cve-2026-44673-cesnet-libyang-heap-buffer-overflow-in-lyb-read-string) (high, CVSS 7.5, published 14 May 2026) ## Most severe CESNET vulnerabilities - [CVE-2026-122130: CESNET ipfixcol2 integer overflow in Forwarder plugin](https://junglewise.ai/threats/cve-2026-122130-cesnet-ipfixcol2-2-3-0-before-2-9-0-contains-an-integer-overflow) (high, CVSS 8.2, published 4 Nov 2026) - [CVE-2026-44673: CESNET libyang heap buffer overflow in lyb_read_string](https://junglewise.ai/threats/cve-2026-44673-cesnet-libyang-heap-buffer-overflow-in-lyb-read-string) (high, CVSS 7.5, published 14 May 2026) - [CVE-2026-122127: CESNET ipfixcol2 heap buffer overflow in LZ4 decompression](https://junglewise.ai/threats/cve-2026-122127-cesnet-ipfixcol2-2-7-1-before-2-9-0-contains-a-heap-based-buffer) (high, CVSS 7.5, published 4 Nov 2026) - [CVE-2026-41401: CESNET libyang heap use-after-free in lyd_parser_set_data_flags](https://junglewise.ai/threats/cve-2026-41401-cesnet-libyang-heap-use-after-free-in-lyd-parser-set-data-flags) (medium, CVSS 6.5, published 26 May 2026) - [CVE-2026-122129: CESNET ipfixcol2 memory exhaustion in LZ4 decoder](https://junglewise.ai/threats/cve-2026-122129-cesnet-ipfixcol2-2-7-1-before-2-9-0-contains-a-memory-allocation) (medium, CVSS 5.3, published 4 Nov 2026) - [CVE-2026-115327: libyang uninitialized pointer free in NETCONF RPC parsing](https://junglewise.ai/threats/cve-2026-115327-libyang-through-6-4-13-contains-an-uninitialized-pointer-free) (medium, CVSS 5.3, published 22 Oct 2026) - [CVE-2026-63201: Netopeer2 format string vulnerability in RPC handling](https://junglewise.ai/threats/cve-2026-63201-netopeer2-is-a-server-for-implementing-network-configuration) (info, published 30 Oct 2026) ## Vulnerabilities per week 5 vulnerabilities in the last four weeks, up from none in the four before. | Week of | Vulns | Critical | Exploited | | --- | --- | --- | --- | | 17 Aug 2026 | 0 | 0 | 0 | | 24 Aug 2026 | 0 | 0 | 0 | | 31 Aug 2026 | 0 | 0 | 0 | | 7 Sep 2026 | 0 | 0 | 0 | | 14 Sep 2026 | 0 | 0 | 0 | | 21 Sep 2026 | 0 | 0 | 0 | | 28 Sep 2026 | 0 | 0 | 0 | | 5 Oct 2026 | 0 | 0 | 0 | | 12 Oct 2026 | 0 | 0 | 0 | | 19 Oct 2026 | 1 | 0 | 0 | | 26 Oct 2026 | 1 | 0 | 0 | | 2 Nov 2026 | 3 | 0 | 0 | | 9 Nov 2026 | 0 | 0 | 0 | ## CESNET technologies - [CESNET Ipfixcol2](https://junglewise.ai/threats/technologies/ipfixcol2): 3 vulnerabilities - [CESNET Libyang](https://junglewise.ai/threats/technologies/libyang): 3 vulnerabilities ## Sources NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories. Rebuilt every hour. Cite as: Junglewise Threat Intelligence, "CESNET vulnerabilities", https://junglewise.ai/threats/vendors/cesnet, 12 November 2026.