CVE-2022-20678

highpriority · track · 30EPSS 0.010 · 61 %ileEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.96% (61st) EPSS
CVSS 7.8 · high
Is it mine?
276 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

A vulnerability in the AppNav-XE feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of certain TCP segments. An attacker could exploit this vulnerability by sending a stream of crafted TCP traffic at a high rate through an interface of an affected device. That interface would need to have AppNav interception enabled. A successful exploit could allow the attacker to cause the device to reload.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

8.6
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–8.6

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.18.6highAV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · ENISA EU
v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · psirt@cisco.com USexploitability 3.9 · impact 4
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · Cisco PSIRT US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-755USprimaryCWE-413USCWE-413US
05

affected products (276)

Products and version ranges known to be affected.

showing 20 of 276
06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-appnav-xe-dos-j5MXTR4Cisco IOS XE Software AppNav-XE Denial of Service Vulnerability2022-04-13csaf · cisco_csafUS

    A vulnerability in the AppNav-XE feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. This vulnerability is due to the incorrect handling of certain TCP segments. An attacker could exploit this vulnerability by sending a stream of crafted TCP traffic at a high rate through an interface of an affected device. That interface would need to have AppNav interception enabled. A successful exploit could allow the attacker to cause the device to reload. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the April 2022 release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: April 2022 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication. ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74561"]

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafNVDCVE.orgMITRE
published 2022-04-15modified 2026-06-17
10

references (6)

External citations — patches, advisories, analysis.

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