PLATEAUMinimal movement since 2026-08-06, 53 days at 0.00, as of 2026-09-28. arc-rules@v1
Foresight · where to check next
No weakness class or product neighbourhood is held for this record, so this index cannot name anywhere to check next. That is an absence in the record, not a finding about the software.
Color is a claim, not decoration:the hostile worldthe defenseno signal
Running Cisco IOS XE Software? Check your version
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Harm, if it fires from the vector and the weakness
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Reachnetwork-reachable · no privileges required · no user interaction · low attack complexityreceipt
ImpactComplete availability loss, with impact beyond the vulnerable componentreceipt
Weakness classCWE-691 Insufficient Control Flow Managementreceipt
Published consequencesCWE-691: Other: Alter Execution Logiccwe-consequences@4.20
CISA KEV & Federal Remediation Deadline from the record and CISA
The fix, and how long it's been waiting.
Fixed inNo fix version in held sources, as the index stood on 28 Sep 2026.
Patch available sinceNo dated patch-availability record in held sources. The index holds reference URLs without dates and only the current revision of the CVE record, so the day a fix first existed cannot be derived. Only the versions it landed in.
BOD 26-04 deadlineIf the system is reachable from the internet: 14 days. If not: fix at the next system upgrade.derived
Show full BOD 26-04 deadline
CISA has not scored it, so the directive's own defaults apply: automatable no, technical impact total. Calendar days from the KEV listing or from when you find it on a system, whichever is first. Federal agencies are bound from 7 Dec 2026, and contracts often carry it to suppliers. The directive and its table
A rung lights from a row in the index, never from an assessment. "Held sources" is the true scope of the claim: this index reads the CVE record, NVD, CISA KEV, FIRST's EPSS and public proof-of-concept repositories, and it does not observe attacks.
Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$14,300over the next 30 days, if this record is yours
Movementno material movementthe record holds only daily drift and scoring model releases
Basisassumeda published average, not your estate
$14,300 = $4.99M incident cost x 0.6121449559255632 exposure x 0.00467 likelihood
udv@v1 · unaudited · wrong for you until you say what you run
$4.99M is the cost of a breach that happened, from IBM Cost of a Data Breach Report 2026, global average. It is not the value of any asset of yours. That average already covers breaches of every severity, so scaling it by exposure understates a partial-impact record. That is an assumption, not a measurement. Your own asset value goes in the decision record.
Attack path
What it is stated by the CNA
As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE Software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.
The vulnerabilities tracked by CVE-2026-20271 are related to insufficient control flow management issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-691.
receipt
NVD's analysis a second authority
weakness
CWE-691
affected versions
cisco ios xe 16.6.2; cisco ios xe 16.6.3; cisco ios xe 16.6.4; and 264 more, listed in full below
4 observations held. A highlighted step crossed a promotion threshold. A step marked with a scoring model moved because the instrument was replaced, not because the vulnerability changed. receipt
The full biography
The record had been public for 1 month when this index was last written.
Published 2026-08-05 receipt · Index as of 2026-09-28 derived
Siblings and hubs
Records related to this one
No record cites this identifier and it carries no alias. The advisory that covers it is below.