CVE-2025-64438 | Fast-DDS: Unbounded GAP range triggers OOM DoS under RELIABLE QoS

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 remotely triggerable Out-of-Memory (OOM) denial-of-service exists in Fast -DDS when processing RTPS GAP submessages under RELIABLE QoS. By sending a tiny GAP packet with a huge gap range (`gapList .base - gapStart`), an attacker drives `StatefulReader::processGapMsg()` into an unbounded loop that inserts millions of s equence numbers into `WriterProxy::changes_received_` (`std::set`), causing multi-GB heap growth and process termination. No authentication is required beyond network reachability to the reader on the DDS domain. In environments without an RSS limit (non-ASan / unlimited), memory consumption was observed to rise to ~64 GB. Versions 3.4.1, 3.3.1, and 2.6.11 patch t he issue.

Published: 2026-02-03 Last update: 2026-02-18 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2025-64438 is rated Low Risk (9.1/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.03%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-64438

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-04 0.03%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-64438

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
1.7 4.0 LOW
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:P)
Additional preconditions must be present for exploitation.
Privileges required (PR:N)
No privileges are required.
User interaction (UI:N)
No user interaction is required.
Vulnerable system confidentiality impact (VC:N)
No confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:L)
Limited availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:N)
No confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:U)
Unreported: no public PoC, no reported exploitation, and no known simplification tools.
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:X)
Not evaluated.
Automatable (supplemental) (AU:X)
Not evaluated.
Recovery (supplemental) (R:X)
Not evaluated.
Value density (supplemental) (V:X)
Not evaluated.
Vulnerability response effort (supplemental) (RE:X)
Not evaluated.
Provider urgency (supplemental) (U:X)
Not evaluated.
[email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]

Weakness enumeration for CVE-2025-64438

OS Trackers for CVE-2025-64438

vendor priority summary link
debian not yet assigned CVE-2025-64438 not yet assigned priority: Debian including 1 source packages (fastdds), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 5. https://security-tracker.debian.org/tracker/CVE-2025-64438
ubuntu medium CVE-2025-64438 medium priority: Ubuntu including 1 source packages (fastdds), 5 status rows across 5 suites (jammy, noble, plucky, questing, upstream): needs-triage 4, ignored 1. https://ubuntu.com/security/CVE-2025-64438

Affected software / configurations for CVE-2025-64438

Vendor Product Version Raw CPE
eprosima fast_dds < 2.6.11 cpe:2.3:a:eprosima:fast_dds:*:*:*:*:*:*:*:*
eprosima fast_dds >= 3.0.0, < 3.3.1 cpe:2.3:a:eprosima:fast_dds:*:*:*:*:*:*:*:*
eprosima fast_dds 3.4.0 cpe:2.3:a:eprosima:fast_dds:3.4.0:*:*:*:*:*:*:*

References for CVE-2025-64438

cvelogic Threat Intelligence