CVE-2026-20267Network attack vector

Unauthenticated device compromise

Published Aug 5, 2026 · Updated Aug 5, 2026

Improper access control in Cisco IOS XE Software allows remote attackers to compromise confidentiality, integrity, and availability. Cisco groups multiple underlying bugs under CWE-284 and has not published their affected components or incorrect authorization operations. The issues are network-reachable without privileges or user interaction, require high attack complexity, and can fully compromise a device.

CVSS severity9.0
Critical
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Improper access control in Cisco IOS XE Software allows remote attackers to compromise confidentiality, integrity, and availability. Cisco groups multiple underlying bugs under CWE-284 and has not published their affected components or incorrect authorization operations. The issues are network-reachable without privileges or user interaction, require high attack complexity, and can fully compromise a device.

The record

CVE
CVE-2026-20267
Published
Aug 5, 2026
Updated
Aug 5, 2026
Vendor
ClamAV
Product
Cisco IOS XE Software
Classifications
CWE-284
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 5, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=16.10.1
  2. Affected versionversion=16.10.1a
  3. Affected versionversion=16.10.1b
  4. Affected versionversion=16.10.1c
  5. Affected versionversion=16.10.1d
  6. Affected versionversion=16.10.1e
  7. Affected versionversion=16.10.1f
  8. Affected versionversion=16.10.1g
  9. Affected versionversion=16.10.1s
  10. Affected versionversion=16.10.2
  11. Affected versionversion=16.10.3
  12. Affected versionversion=16.11.1
  13. Affected versionversion=16.11.1a
  14. Affected versionversion=16.11.1b
  15. Affected versionversion=16.11.1c
  16. Affected versionversion=16.11.1s
  17. Affected versionversion=16.11.2
  18. Affected versionversion=16.12.1
  19. Affected versionversion=16.12.10
  20. Affected versionversion=16.12.10a
  21. Affected versionversion=16.12.11
  22. Affected versionversion=16.12.12
  23. Affected versionversion=16.12.13
  24. Affected versionversion=16.12.14
  25. Affected versionversion=16.12.15
  26. Affected versionversion=16.12.16
  27. Affected versionversion=16.12.1a
  28. Affected versionversion=16.12.1c
  29. Affected versionversion=16.12.1s
  30. Affected versionversion=16.12.1t
  31. Affected versionversion=16.12.1w
  32. Affected versionversion=16.12.1x
  33. Affected versionversion=16.12.1y
  34. Affected versionversion=16.12.1z
  35. Affected versionversion=16.12.1z1
  36. Affected versionversion=16.12.1z2
  37. Affected versionversion=16.12.2
  38. Affected versionversion=16.12.2a
  39. Affected versionversion=16.12.2s
  40. Affected versionversion=16.12.2t
  41. Affected versionversion=16.12.3
  42. Affected versionversion=16.12.3a
  43. Affected versionversion=16.12.3s
  44. Affected versionversion=16.12.4
  45. Affected versionversion=16.12.4a
  46. Affected versionversion=16.12.5
  47. Affected versionversion=16.12.5a
  48. Affected versionversion=16.12.5b
  49. Affected versionversion=16.12.6
  50. Affected versionversion=16.12.6a
  51. Affected versionversion=16.12.7
  52. Affected versionversion=16.12.8
  53. Affected versionversion=16.12.9
  54. Affected versionversion=16.6.10
  55. Affected versionversion=16.6.2
  56. Affected versionversion=16.6.3
  57. Affected versionversion=16.6.4
  58. Affected versionversion=16.6.4a
  59. Affected versionversion=16.6.4s
  60. Affected versionversion=16.6.5
  61. Affected versionversion=16.6.5a
  62. Affected versionversion=16.6.5b
  63. Affected versionversion=16.6.6
  64. Affected versionversion=16.6.7
  65. Affected versionversion=16.6.7a
  66. Affected versionversion=16.6.8
  67. Affected versionversion=16.6.9
  68. Affected versionversion=16.7.1
  69. Affected versionversion=16.7.1a
  70. Affected versionversion=16.7.1b
  71. Affected versionversion=16.7.2
  72. Affected versionversion=16.7.3
  73. Affected versionversion=16.7.4
  74. Affected versionversion=16.8.1
  75. Affected versionversion=16.8.1a
  76. Affected versionversion=16.8.1b
  77. Affected versionversion=16.8.1c
  78. Affected versionversion=16.8.1d
  79. Affected versionversion=16.8.1e
  80. Affected versionversion=16.8.1s
  81. Affected versionversion=16.8.2
  82. Affected versionversion=16.8.3
  83. Affected versionversion=16.9.1
  84. Affected versionversion=16.9.1a
  85. Affected versionversion=16.9.1b
  86. Affected versionversion=16.9.1c
  87. Affected versionversion=16.9.1d
  88. Affected versionversion=16.9.1s
  89. Affected versionversion=16.9.2
  90. Affected versionversion=16.9.2a
  91. Affected versionversion=16.9.2s
  92. Affected versionversion=16.9.3
  93. Affected versionversion=16.9.3a
  94. Affected versionversion=16.9.3h
  95. Affected versionversion=16.9.3s
  96. Affected versionversion=16.9.4
  97. Affected versionversion=16.9.4c
  98. Affected versionversion=16.9.5
  99. Affected versionversion=16.9.5f
  100. Affected versionversion=16.9.6
  101. Affected versionversion=16.9.7
  102. Affected versionversion=16.9.8
  103. Affected versionversion=16.9.8a
  104. Affected versionversion=16.9.8b
  105. Affected versionversion=17.10.1
  106. Affected versionversion=17.10.1a
  107. Affected versionversion=17.10.1b
  108. Affected versionversion=17.1.1
  109. Affected versionversion=17.11.1
  110. Affected versionversion=17.11.1a
  111. Affected versionversion=17.1.1a
  112. Affected versionversion=17.1.1s
  113. Affected versionversion=17.1.1t
  114. Affected versionversion=17.1.2
  115. Affected versionversion=17.12.1
  116. Affected versionversion=17.12.1a
  117. Affected versionversion=17.12.1w
  118. Affected versionversion=17.12.1x
  119. Affected versionversion=17.12.1y
  120. Affected versionversion=17.12.1z
  121. Affected versionversion=17.12.1z1
  122. Affected versionversion=17.12.1z2
  123. Affected versionversion=17.12.1z3
  124. Affected versionversion=17.12.1z4
  125. Affected versionversion=17.12.1z5
  126. Affected versionversion=17.12.1z6
  127. Affected versionversion=17.12.2
  128. Affected versionversion=17.12.2a
  129. Affected versionversion=17.12.3
  130. Affected versionversion=17.12.3a
  131. Affected versionversion=17.12.4
  132. Affected versionversion=17.12.4a
  133. Affected versionversion=17.12.4b
  134. Affected versionversion=17.12.5
  135. Affected versionversion=17.12.5a
  136. Affected versionversion=17.12.5b
  137. Affected versionversion=17.12.5c
  138. Affected versionversion=17.12.5d
  139. Affected versionversion=17.12.6
  140. Affected versionversion=17.12.6a
  141. Affected versionversion=17.12.6b
  142. Affected versionversion=17.12.7
  143. Affected versionversion=17.12.7a
  144. Affected versionversion=17.12.7b
  145. Affected versionversion=17.1.3
  146. Affected versionversion=17.13.1
  147. Affected versionversion=17.13.1a
  148. Affected versionversion=17.14.1
  149. Affected versionversion=17.14.1a
  150. Affected versionversion=17.15.1
  151. Affected versionversion=17.15.1a
  152. Affected versionversion=17.15.1b
  153. Affected versionversion=17.15.1w
  154. Affected versionversion=17.15.1x
  155. Affected versionversion=17.15.1y
  156. Affected versionversion=17.15.2
  157. Affected versionversion=17.15.2a
  158. Affected versionversion=17.15.2b
  159. Affected versionversion=17.15.2c
  160. Affected versionversion=17.15.3
  161. Affected versionversion=17.15.3a
  162. Affected versionversion=17.15.3b
  163. Affected versionversion=17.15.4
  164. Affected versionversion=17.15.4a
  165. Affected versionversion=17.15.4b
  166. Affected versionversion=17.15.4c
  167. Affected versionversion=17.15.4d
  168. Affected versionversion=17.15.4s1
  169. Affected versionversion=17.15.5
  170. Affected versionversion=17.15.5a
  171. Affected versionversion=17.15.7
  172. Affected versionversion=17.16.1
  173. Affected versionversion=17.16.1a
  174. Affected versionversion=17.17.1
  175. Affected versionversion=17.18.1
  176. Affected versionversion=17.18.1a
  177. Affected versionversion=17.18.1w
  178. Affected versionversion=17.18.1x
  179. Affected versionversion=17.18.1y
  180. Affected versionversion=17.18.1z
  181. Affected versionversion=17.18.2
  182. Affected versionversion=17.18.3
  183. Affected versionversion=17.18.3a
  184. Affected versionversion=17.2.1
  185. Affected versionversion=17.2.1a
  186. Affected versionversion=17.2.1r
  187. Affected versionversion=17.2.1v
  188. Affected versionversion=17.2.2
  189. Affected versionversion=17.2.3
  190. Affected versionversion=17.3.1
  191. Affected versionversion=17.3.1a
  192. Affected versionversion=17.3.1w
  193. Affected versionversion=17.3.1x
  194. Affected versionversion=17.3.1z
  195. Affected versionversion=17.3.2
  196. Affected versionversion=17.3.2a
  197. Affected versionversion=17.3.3
  198. Affected versionversion=17.3.3a
  199. Affected versionversion=17.3.4
  200. Affected versionversion=17.3.4a
  201. Affected versionversion=17.3.4b
  202. Affected versionversion=17.3.4c
  203. Affected versionversion=17.3.5
  204. Affected versionversion=17.3.5a
  205. Affected versionversion=17.3.5b
  206. Affected versionversion=17.3.6
  207. Affected versionversion=17.3.7
  208. Affected versionversion=17.3.8
  209. Affected versionversion=17.3.8a
  210. Affected versionversion=17.4.1
  211. Affected versionversion=17.4.1a
  212. Affected versionversion=17.4.1b
  213. Affected versionversion=17.4.1c
  214. Affected versionversion=17.4.2
  215. Affected versionversion=17.4.2a
  216. Affected versionversion=17.5.1
  217. Affected versionversion=17.5.1a
  218. Affected versionversion=17.6.1
  219. Affected versionversion=17.6.1a
  220. Affected versionversion=17.6.1x
  221. Affected versionversion=17.6.1z
  222. Affected versionversion=17.6.1z1
  223. Affected versionversion=17.6.2
  224. Affected versionversion=17.6.3
  225. Affected versionversion=17.6.3a
  226. Affected versionversion=17.6.4
  227. Affected versionversion=17.6.5
  228. Affected versionversion=17.6.5a
  229. Affected versionversion=17.6.6
  230. Affected versionversion=17.6.6a
  231. Affected versionversion=17.6.7
  232. Affected versionversion=17.6.8
  233. Affected versionversion=17.6.8a
  234. Affected versionversion=17.7.1
  235. Affected versionversion=17.7.1a
  236. Affected versionversion=17.7.1b
  237. Affected versionversion=17.7.2
  238. Affected versionversion=17.8.1
  239. Affected versionversion=17.8.1a
  240. Affected versionversion=17.9.1
  241. Affected versionversion=17.9.1a
  242. Affected versionversion=17.9.1w
  243. Affected versionversion=17.9.1x
  244. Affected versionversion=17.9.1x1
  245. Affected versionversion=17.9.1y
  246. Affected versionversion=17.9.1y1
  247. Affected versionversion=17.9.2
  248. Affected versionversion=17.9.2a
  249. Affected versionversion=17.9.3
  250. Affected versionversion=17.9.3a
  251. Affected versionversion=17.9.4
  252. Affected versionversion=17.9.4a
  253. Affected versionversion=17.9.5
  254. Affected versionversion=17.9.5a
  255. Affected versionversion=17.9.5b
  256. Affected versionversion=17.9.5c
  257. Affected versionversion=17.9.5d
  258. Affected versionversion=17.9.5e
  259. Affected versionversion=17.9.5f
  260. Affected versionversion=17.9.6
  261. Affected versionversion=17.9.6a
  262. Affected versionversion=17.9.7
  263. Affected versionversion=17.9.7a
  264. Affected versionversion=17.9.7b
  265. Affected versionversion=17.9.8
  266. Affected versionversion=17.9.9
  267. Affected versionversion=26.1.1
  268. Affected versionversion=26.1.1a

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco IOS XE Softwareversion=16.10.1; version=16.10.1a; version=16.10.1b; version=16.10.1c; version=16.10.1d; version=16.10.1e; version=16.10.1f; version=16.10.1g; version=16.10.1s; version=16.10.2; version=16.10.3; version=16.11.1; version=16.11.1a; version=16.11.1b; version=16.11.1c; version=16.11.1s; version=16.11.2; version=16.12.1; version=16.12.10; version=16.12.10a; version=16.12.11; version=16.12.12; version=16.12.13; version=16.12.14; version=16.12.15; version=16.12.16; version=16.12.1a; version=16.12.1c; version=16.12.1s; version=16.12.1t; version=16.12.1w; version=16.12.1x; version=16.12.1y; version=16.12.1z; version=16.12.1z1; version=16.12.1z2; version=16.12.2; version=16.12.2a; version=16.12.2s; version=16.12.2t; version=16.12.3; version=16.12.3a; version=16.12.3s; version=16.12.4; version=16.12.4a; version=16.12.5; version=16.12.5a; version=16.12.5b; version=16.12.6; version=16.12.6a; version=16.12.7; version=16.12.8; version=16.12.9; version=16.6.10; version=16.6.2; version=16.6.3; version=16.6.4; version=16.6.4a; version=16.6.4s; version=16.6.5; version=16.6.5a; version=16.6.5b; version=16.6.6; version=16.6.7; version=16.6.7a; version=16.6.8; version=16.6.9; version=16.7.1; version=16.7.1a; version=16.7.1b; version=16.7.2; version=16.7.3; version=16.7.4; version=16.8.1; version=16.8.1a; version=16.8.1b; version=16.8.1c; version=16.8.1d; version=16.8.1e; version=16.8.1s; version=16.8.2; version=16.8.3; version=16.9.1; version=16.9.1a; version=16.9.1b; version=16.9.1c; version=16.9.1d; version=16.9.1s; version=16.9.2; version=16.9.2a; version=16.9.2s; version=16.9.3; version=16.9.3a; version=16.9.3h; version=16.9.3s; version=16.9.4; version=16.9.4c; version=16.9.5; version=16.9.5f; version=16.9.6; version=16.9.7; version=16.9.8; version=16.9.8a; version=16.9.8b; version=17.10.1; version=17.10.1a; version=17.10.1b; version=17.1.1; version=17.11.1; version=17.11.1a; version=17.1.1a; version=17.1.1s; version=17.1.1t; version=17.1.2; version=17.12.1; version=17.12.1a; version=17.12.1w; version=17.12.1x; version=17.12.1y; version=17.12.1z; version=17.12.1z1; version=17.12.1z2; version=17.12.1z3; version=17.12.1z4; version=17.12.1z5; version=17.12.1z6; version=17.12.2; version=17.12.2a; version=17.12.3; version=17.12.3a; version=17.12.4; version=17.12.4a; version=17.12.4b; version=17.12.5; version=17.12.5a; version=17.12.5b; version=17.12.5c; version=17.12.5d; version=17.12.6; version=17.12.6a; version=17.12.6b; version=17.12.7; version=17.12.7a; version=17.12.7b; version=17.1.3; version=17.13.1; version=17.13.1a; version=17.14.1; version=17.14.1a; version=17.15.1; version=17.15.1a; version=17.15.1b; version=17.15.1w; version=17.15.1x; version=17.15.1y; version=17.15.2; version=17.15.2a; version=17.15.2b; version=17.15.2c; version=17.15.3; version=17.15.3a; version=17.15.3b; version=17.15.4; version=17.15.4a; version=17.15.4b; version=17.15.4c; version=17.15.4d; version=17.15.4s1; version=17.15.5; version=17.15.5a; version=17.15.7; version=17.16.1; version=17.16.1a; version=17.17.1; version=17.18.1; version=17.18.1a; version=17.18.1w; version=17.18.1x; version=17.18.1y; version=17.18.1z; version=17.18.2; version=17.18.3; version=17.18.3a; version=17.2.1; version=17.2.1a; version=17.2.1r; version=17.2.1v; version=17.2.2; version=17.2.3; version=17.3.1; version=17.3.1a; version=17.3.1w; version=17.3.1x; version=17.3.1z; version=17.3.2; version=17.3.2a; version=17.3.3; version=17.3.3a; version=17.3.4; version=17.3.4a; version=17.3.4b; version=17.3.4c; version=17.3.5; version=17.3.5a; version=17.3.5b; version=17.3.6; version=17.3.7; version=17.3.8; version=17.3.8a; version=17.4.1; version=17.4.1a; version=17.4.1b; version=17.4.1c; version=17.4.2; version=17.4.2a; version=17.5.1; version=17.5.1a; version=17.6.1; version=17.6.1a; version=17.6.1x; version=17.6.1z; version=17.6.1z1; version=17.6.2; version=17.6.3; version=17.6.3a; version=17.6.4; version=17.6.5; version=17.6.5a; version=17.6.6; version=17.6.6a; version=17.6.7; version=17.6.8; version=17.6.8a; version=17.7.1; version=17.7.1a; version=17.7.1b; version=17.7.2; version=17.8.1; version=17.8.1a; version=17.9.1; version=17.9.1a; version=17.9.1w; version=17.9.1x; version=17.9.1x1; version=17.9.1y; version=17.9.1y1; version=17.9.2; version=17.9.2a; version=17.9.3; version=17.9.3a; version=17.9.4; version=17.9.4a; version=17.9.5; version=17.9.5a; version=17.9.5b; version=17.9.5c; version=17.9.5d; version=17.9.5e; version=17.9.5f; version=17.9.6; version=17.9.6a; version=17.9.7; version=17.9.7a; version=17.9.7b; version=17.9.8; version=17.9.9; version=26.1.1; version=26.1.1a

Published CVSS scores

9.0Cisco Systems, Inc.CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo