Is there a public exploit for CVE-2026-122129?

No public exploit for CVE-2026-122129 was found in Exploit-DB, Metasploit, Nuclei templates or public proof-of-concept repositories. That is an absence of evidence rather than proof that none exists.

How severe is CVE-2026-122129?

CVE-2026-122129 scores CVSS 6.9 (v4.0), rated medium.

What does CVE-2026-122129 affect?

CVE-2026-122129 affects CESNET ipfixcol2.

6.9 Medium

CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::readstartheader() that allows unauthenticated…

CVE-2026-122129

CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::readstartheader() that allows unauthenticated attackers to exhaust memory by declaring unbounded ring buffer sizes. Attackers can open TCP connections sending LZ4 start headers with very large buffer sizes, forcing up to 4 GiB allocations per connection and denying collector service.

Assessment

CVSS: 6.9 (v4.0)
Severity: Medium
Known exploited: Not listed in CISA KEV
Exploit availability: Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
Published: 4 November 2026
Last updated: 4 November 2026
Affected: CESNET · ipfixcol2
Assigner: VulnCheck

CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

At the source

EUVD (ENISA)

References

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