CVE-2025-20248VulnerabilityPublished 10 Sep 2025Updated 26 Feb 2026

CVE-2025-20248: Cisco IOS XR Software · Improper Verification of Cryptographic Signature

Affects Cisco IOS XR SoftwareSource CVE Database V5

Not known to be exploited · CVSS 6.0 Medium.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

6.0Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.09% chance of exploitation in 30 days – higher than 0% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N

Attack Vector: Local
Attack Complexity: Low
Privileges Required: High
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: High: The attacker is authorized with (i.e., requires) privileges that provide significant (e.g., administrative) control over the vulnerable component that could affect component-wide settings and files.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 10 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Cisco Cisco IOS XR Software	Affected =6.5.3 =6.5.29 =6.5.1 =6.6.1 =6.5.2 =6.5.92 =6.5.15 =6.6.2 =7.0.1 =6.6.25 =6.5.26 =6.6.11 =6.5.25 =6.5.28 =6.5.93 =6.6.12 =6.5.90 =7.0.0 =7.1.1 =7.0.90 =6.6.3 =6.7.1 =7.0.2 =7.1.15 =7.2.0 =7.2.1 =7.1.2 =6.7.2 =7.1.25 =6.6.4 =7.3.1 =7.1.3 =6.7.3 =7.4.1 =7.2.2 =6.5.31 =6.8.1 =7.4.15 =6.5.32 =7.3.2 =7.5.1 =7.4.16 =7.3.27 =7.6.1 =7.5.2 =7.6.15 =7.3.3 =7.7.1 =6.8.2 =7.3.4 =7.4.2 =6.7.35 =6.9.1 =7.6.2 =7.8.1 =7.5.3 =7.7.2 =6.9.2 =7.9.1 =7.8.2 =7.5.4 =6.5.33 =7.8.22 =7.10.1 =7.7.21 =7.9.2 =7.3.5 =7.5.5 =7.11.1 =7.9.21 =7.10.2 =7.6.3 =24.1.1 =7.3.6 =7.11.2 =24.2.1 =24.1.2 =24.2.11 =24.3.1 =24.4.1 =24.2.2 =7.8.23 =7.11.21 =24.2.20 =24.3.2 =24.4.10 =6.5.35 =24.4.15 =6.5.351 =6.5.352	Fixed in–

AI-suggested

Organizations should immediately identify and inventory all Cisco IOS XR devices running affected versions. Cisco is expected to release patches or updates addressing this vulnerability; applying these updates promptly is critical. Until patches are available, restrict root-system access strictly to trusted administrators and implement robust internal access controls and monitoring to detect unauthorized privilege escalations. Employ multi-factor authentication and limit the number of users with root privileges. Validate all software images before installation and consider using out-of-band verification methods to ensure image integrity. Network segmentation and strict change management policies can reduce the risk of unauthorized image installation. Regularly audit device configurations and logs for signs of tampering or unauthorized software installations. Finally, maintain up-to-date backups and incident response plans tailored to network infrastructure compromise scenarios.

Description

A vulnerability in the installation process of Cisco IOS XR Software could allow an authenticated, local attacker to bypass Cisco IOS XR Software image signature verification and load unsigned software on an affected device. To exploit this vulnerability, the attacker must have root-system privileges on the affected device. This vulnerability is due to incomplete validation of files during the installation of an .iso file. An attacker could exploit this vulnerability by modifying contents of the .iso image and then installing and activating it on the device. A successful exploit could allow the attacker to load an unsigned file as part of the image activation process.

Impact

The vulnerability poses a significant risk to organizations relying on Cisco IOS XR Software for routing and network infrastructure, especially large enterprises and service providers. If exploited, attackers with root access can load unsigned and potentially malicious software, compromising device confidentiality and integrity. This could lead to unauthorized data interception, network manipulation, or persistent backdoors within critical network devices. Although availability impact is not directly indicated, compromised devices could be leveraged for further attacks or cause network disruptions indirectly. The requirement for root privileges limits the attack surface but elevates the risk if internal threat actors or attackers who have already gained privileged access exploit this flaw. Given Cisco IOS XR's widespread deployment in critical backbone and edge networks globally, the vulnerability could have cascading effects on network security and trustworthiness.

References

sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xrsig-UY4zRUCG (opens in a new tab)

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Feb 2026, 22:21 UTC

Technical details

References

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