Report · Reddit CybersecurityAbout CVE-2026-20262Published 16 Jun 2026

Cisco Patches Another SD-WAN Zero-Day Exploited in Attacks

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Authoritative record:CVE-2026-20262· Medium 6.5

Exploited in the wild · KEV due 29 Jun 2026 : apply the vendor's fix or mitigations to Catalyst SD-WAN Manager now.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

6.5Medium

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

KEV deadline: 29 Jun 2026 US federal agencies must patch by this date; a sensible deadline for everyone else. Other KEV due dates

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

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

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: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
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: None: There is no loss of confidentiality within the impacted component.
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

t = 0 is the CVE’s publication on cve.org

Disclosed: evidence found.
CVE published 15 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: evidence found.
Listed in CISA KEV the same day as disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

CVE published
on cve.org
15 Jun 202616:21 UTC, t = 0
Added to CISA KEV (opens in a new tab)
exploitation confirmed
15 Jun 2026, the same day as disclosure
In Threat Radar
record ingested
16 Jun 202600:00 UTC, 8 hours after disclosure
KEV remediation due
US federal deadline
29 Jun 2026, 14 days after disclosure

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), 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

Affected software

Product	Affected	Fixed in
CiscoCisco Catalyst SD-WAN Manager	Affected 17.2.4 – 26.1.1.1_LI_Images 371 affected builds	Fixed in–

AI-suggested

Cisco has released official patches to address CVE-2026-20262. Organizations using Catalyst SD-WAN Manager should apply these patches immediately. CISA mandates remediation by June 29, 2026, for federal agencies. Since exploitation requires valid credentials with write access, organizations should also review and restrict access controls accordingly. Patch status is confirmed as fixed by Cisco's advisory.

Discussion

Cisco disclosed a zero-day vulnerability (CVE-2026-20262) in Catalyst SD-WAN Manager that allows an attacker with valid credentials and write access to send crafted HTTP requests to an API endpoint, enabling arbitrary file write on the underlying operating system. This vulnerability can be leveraged to escalate privileges to root. Cisco discovered the flaw internally and confirmed limited exploitation in targeted attacks. The vulnerability is considered medium severity by Cisco but is rated critical here due to its exploitation and potential impact. Cisco has released patches addressing this issue. The U.S. Cybersecurity and Infrastructure Security Agency (CISA) added this vulnerability to its Known Exploited Vulnerabilities catalog, mandating remediation by June 29, 2026. This is one of multiple SD-WAN vulnerabilities exploited in 2026.

r/cybersecurity (opens in a new tab)u/sunychoudhary0 points0 comments

https://www.securityweek.com/cisco-patches-another-sd-wan-zero-day-exploited-in-attacks/

Links cited in the discussion

https://www.securityweek.com/cisco-patches-another-sd-wan-zero-day-exploited-in-attacks/

Impact

An attacker with valid credentials and write access can exploit this vulnerability to write arbitrary files on the system hosting Catalyst SD-WAN Manager, potentially leading to root privilege escalation. This could allow full control over the affected system. The vulnerability has been exploited in limited, targeted attacks, indicating active threat exploitation. The impact is critical due to the potential for complete system compromise.

References

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Exploitation evidence

Timeline

What to do

Affected software

Discussion

Links cited in the discussion

AI analysisMachine-generated, updated 16 Jun 2026, 07:45 UTC

Public exploits and detectionGitHub proofs of concept

Technical details

References

Community reviews

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