CVE-2025-62603 FastDDS has Out-of-memory while parsing GenericMessage when DDS Security is enabled
Remote attackers can cause denial of service via memory exhaustion in Fast DDS when parsing security messages, requiring DDS Security to be enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-62603?
CVE-2025-62603 is a low-severity denial of service vulnerability in Debian Debian Linux, published on 3 Feb 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Fast DDS is a C++ implementation of the DDS (Data Distribution Service) standard of the OMG (Object Management Group ). ParticipantGenericMessage is the DDS Security control-message container that carries not only the handshake but also on going security-control traffic after the handshake, such as crypto-token exchange, rekeying, re-authentication, and token delivery for newly appearing endpoints. On receive, the CDR parser is invoked first and deserializes the `message_data` (i .e., the `DataHolderSeq`) via the `readParticipantGenericMessage → readDataHolderSeq` path. The `DataHolderSeq` is parsed sequentially: a sequence count (`uint32`), and for each DataHolder the `class_id` string (e.g. `DDS:Auth:PKI-DH:1.0+Req`), string properties (a sequence of key/value pairs), and binary properties (a name plus an octet-vector). The parser operat es at a stateless level and does not know higher-layer state (for example, whether the handshake has already completed), s o it fully unfolds the structure before distinguishing legitimate from malformed traffic. Because RTPS permits duplicates, delays, and retransmissions, a receiver must perform at least minimal structural parsing to check identity and sequence n umbers before discarding or processing a message; the current implementation, however, does not "peek" only at a minimal header and instead parses the entire `DataHolderSeq`. As a result, prior to versions 3.4.1, 3.3.1, and 2.6.11, this parsi ng behavior can trigger an out-of-memory condition and remotely terminate the process. Versions 3.4.1, 3.3.1, and 2.6.11 p atch the issue.
Weakness: CWE-125
Which versions are affected by CVE-2025-62603?
It affects 2 products.
Products include Debian Debian Linux, Eprosima Fast Dds.
How do I fix CVE-2025-62603?
No fix has been published for CVE-2025-62603 yet. Limit exposure of the affected software until one is available.
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-2025-62603 being exploited?
There is no known exploitation of CVE-2025-62603 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as DEBIAN-CVE-2025-62603, UBUNTU-CVE-2025-62603.