CVE-2023-39949 Improper validation of sequence numbers leading to remotely reachable assertion failure

What is CVE-2023-39949?

CVE-2023-39949 is a high-severity denial of service vulnerability in Debian Debian Linux, published on 11 Aug 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

eprosima Fast DDS is a C++ implementation of the Data Distribution Service standard of the Object Management Group. Prior to versions 2.9.1 and 2.6.5, improper validation of sequence numbers may lead to remotely reachable assertion failure. This can remotely crash any Fast-DDS process. Versions 2.9.1 and 2.6.5 contain a patch for this issue.

Weakness: CWE-617

Which versions are affected by CVE-2023-39949?

It affects 2 products.

Products include Debian Debian Linux, Eprosima Fast Dds.

How do I fix CVE-2023-39949?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2023-39949 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-39949 exists.

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All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2023-39949, GHSA-3jv9-j9x3-95cg, UBUNTU-CVE-2023-39949.