CVE-2026-20004High· 7.4▾ TwilightA vulnerability in the TLS library of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to exhaust the available memory of an affected device. This vulnerability is due to improper management of memory resources …
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 40.7 · likelihood 0 · exploitation 0
Need a working PoC? Pro members can cast a request and our team develops one — it lands right here.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
Last analysed / modified upstream
0.2%
A vulnerability in the TLS library of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to exhaust the available memory of an affected device.
This vulnerability is due to improper management of memory resources during TLS connection setup. An attacker could exploit this vulnerability by repeatedly triggering the conditions that cause the memory increase. This could be done in a variety of ways, such as by repeatedly attempting Extensible Authentication Protocol (EAP) authentication when local EAP is enabled on an affected device or by using a machine-in-the-middle attack and resetting TLS connections between the affected device and other devices. A successful exploit could allow the attacker to exhaust the available memory on an affected device, resulting in an unexpected reload and a denial of service (DoS) condition.
ios_xe = 16.9.1ios_xe = 16.9.1aios_xe = 16.9.1bios_xe = 16.9.1sios_xe = 16.9.2ios_xe = 16.9.3ios_xe = 16.9.3aios_xe = 16.9.4ios_xe = 16.9.5ios_xe = 16.9.5fios_xe = 16.9.6ios_xe = 16.9.7ios_xe = 16.9.8ios_xe = 16.10.1ios_xe = 16.10.1aios_xe = 16.10.1bios_xe = 16.10.1cios_xe = 16.10.1dios_xe = 16.10.1eios_xe = 16.10.1fios_xe = 16.10.1gios_xe = 16.10.1sios_xe = 16.10.2ios_xe = 16.10.3ios_xe = 16.11.1ios_xe = 16.11.1aios_xe = 16.11.1bios_xe = 16.11.1sios_xe = 16.11.2ios_xe = 16.12.1ios_xe = 16.12.1aios_xe = 16.12.1cios_xe = 16.12.1sios_xe = 16.12.1tios_xe = 16.12.1wios_xe = 16.12.1xios_xe = 16.12.1yios_xe = 16.12.1z1ios_xe = 16.12.1z2ios_xe = 16.12.2ios_xe = 16.12.2aios_xe = 16.12.2sios_xe = 16.12.3ios_xe = 16.12.3aios_xe = 16.12.3sios_xe = 16.12.4ios_xe = 16.12.4aios_xe = 16.12.5ios_xe = 16.12.5aios_xe = 16.12.5bios_xe = 16.12.6ios_xe = 16.12.6aios_xe = 16.12.7ios_xe = 16.12.8ios_xe = 16.12.9ios_xe = 16.12.10ios_xe = 16.12.10aios_xe = 16.12.11ios_xe = 16.12.12ios_xe = 16.12.13ios_xe = 16.12.14ios_xe = 16.12.15ios_xe = 17.1.1ios_xe = 17.1.1aios_xe = 17.1.1sios_xe = 17.1.1tios_xe = 17.1.3ios_xe = 17.2.1ios_xe = 17.2.1aios_xe = 17.2.1rios_xe = 17.2.1vios_xe = 17.2.2ios_xe = 17.2.3ios_xe = 17.3.1ios_xe = 17.3.1aios_xe = 17.3.1wios_xe = 17.3.1xios_xe = 17.3.1zios_xe = 17.3.2ios_xe = 17.3.2aios_xe = 17.3.3ios_xe = 17.3.4ios_xe = 17.3.4aios_xe = 17.3.4bios_xe = 17.3.4cios_xe = 17.3.5ios_xe = 17.3.5aios_xe = 17.3.5bios_xe = 17.3.6ios_xe = 17.3.7ios_xe = 17.3.8ios_xe = 17.3.8aios_xe = 17.4.1ios_xe = 17.4.1aios_xe = 17.4.1bios_xe = 17.4.2ios_xe = 17.4.2aios_xe = 17.5.1ios_xe = 17.5.1aios_xe = 17.6.1Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-20263High· 8.6A vulnerability in the Blocks Extensible Exchange Protocol (BEEP) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability …
CVE-2026-20084High· 8.6A vulnerability in the DHCP snooping feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause BOOTP packets to be forwarded between VLANs, resulting in a denial of service (DoS) condition
CVE-2026-20104Medium· 6.1A vulnerability in the bootloader of Cisco IOS XE Software for Cisco Catalyst 9200 Series Switches, Cisco Catalyst ESS9300 Embedded Series Switches, Cisco Catalyst IE9310 and IE9320 Rugged Series Switches, and Cisco IE3500 and IE3505 Rug…
CVE-2025-20192High· 7.7A vulnerability in the Internet Key Exchange version 1 (IKEv1) implementation of Cisco IOS XE Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition
CVE-2025-20338Medium· 6.0A vulnerability in the CLI of Cisco IOS XE Software could allow an authenticated, local attacker with administrative privileges to execute arbitrary commands as root on the underlying operating system of an affected device. This vulne…
CVE-2025-20315High· 8.6A vulnerability in the Network-Based Application Recognition (NBAR) feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, causing a denial of service (DoS) condition. T…