cbcvebase.
CVE-2026-20868
published 2026-01-13

CVE-2026-20868: Heap-based buffer overflow in Windows Routing and Remote Access Service (RRAS) allows an unauthorized attacker to execute code over a network.

PriorityP261high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
1.34%
68.1th percentile
Heap-based buffer overflow in Windows Routing and Remote Access Service (RRAS) allows an unauthorized attacker to execute code over a network.

Affected

45 ranges· showing 25
VendorProductVersion rangeFixed in
microsoftwindows_10_1607< 10.0.14393.878310.0.14393.8783
microsoftwindows_10_1809< 10.0.17763.827610.0.17763.8276
microsoftwindows_10_21h2< 10.0.19044.680910.0.19044.6809
microsoftwindows_10_22h2< 10.0.19045.680910.0.19045.6809
microsoftwindows_10_version_1607>= 10.0.14393.0 < 10.0.14393.878310.0.14393.8783
microsoftwindows_10_version_1809>= 10.0.17763.0 < 10.0.17763.827610.0.17763.8276
microsoftwindows_10_version_21h2>= 10.0.19044.0 < 10.0.19044.680910.0.19044.6809
microsoftwindows_10_version_22h2>= 10.0.19045.0 < 10.0.19045.680910.0.19045.6809
microsoftwindows_11_23h2< 10.0.22631.649110.0.22631.6491
microsoftwindows_11_24h2< 10.0.26100.762310.0.26100.7623
microsoftwindows_11_25h2< 10.0.26200.762310.0.26200.7623
microsoftwindows_11_version_22h3>= 10.0.22631.0 < 10.0.22631.649110.0.22631.6491
microsoftwindows_11_version_23h2>= 10.0.22631.0 < 10.0.22631.649110.0.22631.6491
microsoftwindows_11_version_24h2>= 10.0.26100.0 < 10.0.26100.762310.0.26100.7623
microsoftwindows_11_version_25h2>= 10.0.26200.0 < 10.0.26200.762310.0.26200.7623
microsoftwindows_server_2008
microsoftwindows_server_2008_r2_service_pack_1>= 6.1.7601.0 < 6.1.7601.281176.1.7601.28117
microsoftwindows_server_2008_service_pack_2>= 6.0.6003.0 < 6.0.6003.237176.0.6003.23717
microsoftwindows_server_2012
microsoftwindows_server_2012>= 6.2.9200.0 < 6.2.9200.258686.2.9200.25868
microsoftwindows_server_2012_r2>= 6.3.9600.0 < 6.3.9600.229686.3.9600.22968
microsoftwindows_server_2016< 10.0.14393.878310.0.14393.8783
microsoftwindows_server_2016>= 10.0.14393.0 < 10.0.14393.878310.0.14393.8783
microsoftwindows_server_2019< 10.0.17763.827610.0.17763.8276
microsoftwindows_server_2019>= 10.0.17763.0 < 10.0.17763.827610.0.17763.8276

Detection & IOCsextracted from sources · hover to see the quote

  • Attack vector involves a domain-authenticated attacker tricking a domain-joined user into sending a request to a malicious server via the RRAS Snap-in, resulting in the server returning malicious data causing arbitrary code execution on the client system.
  • ·No public exploit exists and exploitation is rated 'Less Likely' by Microsoft as of the patch date. No CISA KEV entry. Patch is available via the referenced KB articles.
  • ·Customer action is required — patching is necessary to remediate this heap-based buffer overflow in Windows RRAS.

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
vendor_msrc8.8HIGH
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