Vulnerability record
CVE-2026-123999
The short answer
CVE-2026-123999 affects nasa-jpl ION-DTN and is rated high (CVSS 8.7). It is not in CISA's KEV catalog; EPSS puts the chance of exploitation in the next 30 days at 0.48%.
What it is
NASA JPL ION-DTN 3.6.2 through 4.2.0 contains a heap-based buffer overflow in the Network Management daemon (nm_mgr) string-formatting logic that allows a malicious or misconfigured agent to trigger an out-of-bounds write by sending deeply nested AMP payloads that exceed fixed-size buffer allocations through unbounded strcat operations. Attackers can transmit oversized AMP reports, tables, or macros over the UDP CLA/AMP path or trigger the flaw locally via interactive UI rendering to crash nm_mgr and cause a denial of service halting telemetry collection and operator visibility.
Weakness: CWE-122.
Severity
8.7 high
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/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
Exploited (CISA KEV)
Not listed
CISA lists confirmed exploitation only
EPSS, next 30 days
0.48%
Higher than 42% of scored CVEs
How it can be exploited
- Attack vector
- Network
- Attack complexity
- Low
- Attack requirements
- None
- Privileges required
- None
- User interaction
- None
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Affected products
ION-DTN. NVD's record lists the exact affected versions.
References
Questions
Is CVE-2026-123999 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog as of 2026-11-11. FIRST's EPSS estimates a 0.48% chance of exploitation in the next 30 days.
How do I fix CVE-2026-123999?
Follow the vendor advisory in the references below. NVD lists the affected versions under its configurations.
From NVD, CISA KEV, FIRST EPSS and OSV.dev, checked . Status on NVD: Deferred. The description is NVD's text, quoted as published.
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