A vulnerability in the handling of an Egress Packet Network Interface (EPNI) Aligner interrupt in Cisco IOS XR Software for Cisco Network Convergence System (NCS) 5500 Series with NC57 line cards and Cisco NCS 5700 Routers and Cisco IOS XR Software for Third Party Software could allow an unauthenticated, remote attacker to cause the network processing unit (NPU) and ASIC to stop processing, preventing traffic from traversing the interface. This vulnerability is due to the corruption of packets in specific cases when an EPNI Aligner interrupt is triggered while an affected device is experiencing heavy transit traffic. An attacker could exploit this vulnerability by sending a continuous flow of crafted packets to an interface of the affected device. A successful exploit could allow the attacker to cause persistent, heavy packet loss, resulting in a denial of service (DoS) condition. Note: If active exploitation of this vulnerability is suspected, contact the Cisco Technical Assistance Center (TAC) or your contracted maintenance provider. Cisco has assigned this security advisory a Security Impact Rating (SIR) of High rather than Medium as the score indicates. This change was made because the affected device operates within a critical network segment where compromise could lead to significant disruption or exposure, thereby elevating the overall risk beyond the base technical severity.
CVE-2026-20118
Score 6.8 from GitHub Security Advisory published 2026-03-11. the CNA's CVSS baseline 6.8; sources differ by 0.0.
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.8
- EG Score
- 6.8(medium)
- EG Risk
- 31(Track)EG Risk 31/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity68% × 45%Exploitation0% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 24%
- KEV
- Not listed
Published
March 11, 2026
Last Modified
June 17, 2026
References (1)
Vendor Advisories for CVE-2026-20118(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 5× in last 7d / 5× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-01 04:15 UTCEPSS rescore
- 2026-07-30 01:30 UTCEPSS rescore
- 2026-07-27 14:13 UTCEPSS rescore
- 2026-07-27 12:52 UTCEG score recompute
- 2026-07-27 12:52 UTCGHSA enrichment
Frequently asked(5)
What is CVE-2026-20118?
When was CVE-2026-20118 disclosed?
Is CVE-2026-20118 actively exploited?
What is the CVSS score of CVE-2026-20118?
How do I remediate CVE-2026-20118?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-20118
Is Your Infrastructure Affected by CVE-2026-20118?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.