CVE-2026-122127highCWE-787

CVE-2026-122127: high-severity vulnerability in CESNET ipfixcol2

CESNET ipfixcol2 2.7.1 before 2.9.0 Heap Buffer Overflow via TCP LZ4 Decoder

Published

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18Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 8.7
CESNET ipfixcol2 2.7.1 before 2.9.0 contains a heap-based buffer overflow in Lz4Decoder.cpp that allows unauthenticated network peers to write past heap buffers. Attackers can declare a small ring buffer_size followed by a large decompressed_size to write up to 65535 controlled bytes and crash the collector.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected products
CESNET · ipfixcol2
Related CVEs — CESNET ipfixcol2

In the same product, most dangerous first.

CVE-2026-122130HIGHCESNET ipfixcol2 2.3.0 before 2.9.0 Buffer Overflow via Forwarder Output PluginEPSS —CVE-2026-122129MEDIUMCESNET ipfixcol2 2.7.1 before 2.9.0 Memory Exhaustion via TCP LZ4 DecoderEPSS —