CVE-2026-20004
published 2026-03-25CVE-2026-20004: 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…
PriorityP337high7.4CVSS 3.1
AVAACLPRNUINSCCNINAH
EPSS
0.18%
7.5th percentile
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.
Affected
181 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
| cisco | cisco_ios_xe_software | — | — |
CVSS provenance
nvdv3.17.4HIGHCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
vendor_cisco7.4HIGH
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Cisco
Cisco IOS XE Software TLS Memory Exhaustion Denial of Service Vulnerability
vendor_cisco·2026-03-25·CVSS 7.4
CVE-2026-20004 [HIGH] CWE-771 Cisco IOS XE Software TLS Memory Exhaustion Denial of Service Vulnerability
Cisco IOS XE Software TLS Memory Exhaustion Denial of Service Vulnerability
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 attacke
Cisco
Cisco IOS XE Software TLS Memory Exhaustion Denial of Service Vulnerability
vendor_cisco·CVSS 3.1
CVE-2026-20004 Cisco IOS XE Software TLS Memory Exhaustion Denial of Service Vulnerability
CVE-2026-20004: Cisco IOS XE Software TLS Memory Exhaustion Denial of Service Vulnerability
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 all
GHSA
GHSA-xp4f-63f5-wmm9: A vulnerability in the TLS library of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to exhaust the available memory of an af
ghsa_unreviewed·2026-03-25
CVE-2026-20004 [HIGH] CWE-771 GHSA-xp4f-63f5-wmm9: A vulnerability in the TLS library of Cisco IOS XE Software could allow an unauthenticated, adjacent attacker to exhaust the available memory of an af
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 unex
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-03-25
Published