VulnerabilityPublished 15 Oct 2025Updated 12 Feb 2026

CVE-2025-20359: Cisco Cyber Vision · Buffer Under-read

Affects Cisco Cyber VisionSource CVE Database V5

Not known to be exploited · CVSS 6.5 Medium : upgrade to 4.3.0 when convenient.

Data as of 26 Oct 2026, 10:12 UTC

CVSS 3.1 base score

6.5Medium

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 41% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 4.3.0

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

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

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

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
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: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 15 Oct 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 26 Oct 2026.

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 or the CVSS exploit maturity 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

Upgrade Cisco Cyber Vision to 4.3.0.

Affected software

Product	Affected	Fixed in
Cisco Cisco Cyber Vision	Affected 3.0.0 – 5.2.1 >=4.2.0 <4.3.0 51 affected builds	Fixed in 4.3.0

AI-suggested

Organizations should immediately inventory Cisco Cyber Vision deployments to identify affected versions. In the interim, network segmentation should be enforced to limit exposure of Cisco Cyber Vision systems to untrusted networks. Deploy strict ingress filtering and firewall rules to block or scrutinize suspicious HTTP traffic that could exploit the Snort 3 HTTP Decoder. Implement anomaly detection to identify unusual HTTP packet patterns targeting industrial monitoring systems. Regularly review and harden the configurations of Cisco Cyber Vision and Snort 3 components, disabling unnecessary protocols or features that parse HTTP headers if feasible. Conduct penetration testing and vulnerability scans focused on this issue to validate mitigations. Additionally, maintain robust incident response plans to quickly address potential DoS or data leakage events. Collaboration with Cisco support and threat intelligence sharing within industry sectors can enhance preparedness.

Description

Multiple Cisco products are affected by a vulnerability in the Snort 3 HTTP Decoder that could allow an unauthenticated, remote attacker to cause the disclosure of possible sensitive data or cause the Snort 3 Detection Engine to crash. This vulnerability is due to an error in the logic of buffer handling when the MIME fields of the HTTP header are parsed. This can result in a buffer under-read. An attacker could exploit this vulnerability by sending crafted HTTP packets through an established connection that is parsed by Snort 3. A successful exploit could allow the attacker to induce one of two possible outcomes: the unexpected restarting of the Snort 3 Detection Engine, which could cause a denial of service (DoS) condition, or information disclosure of sensitive information in the Snort 3 data stream. Due to the under-read condition, it is possible that sensitive information that is not valid connection data could be returned.

Impact

For European organizations, especially those in critical infrastructure sectors such as manufacturing, energy, utilities, and transportation that deploy Cisco Cyber Vision for industrial network monitoring, this vulnerability poses a risk to both operational continuity and data confidentiality. A successful DoS attack could disrupt the Snort 3 Detection Engine, impairing real-time threat detection and response capabilities, potentially allowing other attacks to go unnoticed. The information disclosure aspect, while limited, could expose sensitive operational data or network metadata, which adversaries might leverage for further attacks or industrial espionage. The broad range of affected versions increases the likelihood that many European enterprises have vulnerable deployments. Disruption of industrial monitoring tools can have cascading effects on production processes and safety systems. Additionally, the unauthenticated remote exploitability raises the threat level, as attackers do not need prior access or credentials. This vulnerability could be particularly impactful in countries with advanced industrial sectors and significant Cisco Cyber Vision adoption.

References

sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort3-mime-vulns-tTL8PgVH (opens in a new tab)

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 13 Feb 2026, 06:40 UTC

Technical details

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