CVE-2026-122127
CESNET ipfixcol2 2.7.1 before 2.9.0 contains a heap-based buffer overflow in Lz4Decoder.cpp that…
- Risk score
- 50/100
- CVSS
- 7.5 v3.1
- Published
- 4 Nov 2026
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What to know
- What it is
- 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.
- Affected
- See advisory
- Fix
- Upgrade the product to 2.9.0 or later.
- Exploitation
- No known exploitation
Why it is Yellow
- CVSS 7.5 high
- Remotely exploitable without logging in
References
- https://github.com/CESNET/ipfixcol2
- https://github.com/CESNET/ipfixcol2/blob/v2.8.0/src/plugins/input/tcp/src/Lz4Decoder.cpp#L139-L151
- https://github.com/CESNET/ipfixcol2/commit/fd5cb168efb4b864d33f655174711b2779cef502
- https://github.com/CESNET/ipfixcol2/releases/tag/v2.9.0
- https://www.vulncheck.com/advisories/cesnet-ipfixcol2-2.7.1-before-2.9.0-heap-buffer-overflow-via-tcp-lz4-decoder
Original description
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.
Last activity 4 Nov 2026. Patch Forecast updates every hour.