# What is CVE-2017-6753?

> CVE-2017-6753 is a high-severity flaw (CVSS 8.8) in Webex Meetings Server from Cisco, published on 25 July 2017. It is not on the list of flaws known to be exploited today. The latest forecast puts its chance of use in the next 30 days at 6.0%. If you run an affected version, plan in the vendor’s fix.

Canonical page: https://www.precursorintelligence.com/what-is/cve-2017-6753

## At a glance

- **Verdict:** Plan it in. No sign of exploitation and a low forecast. Patch it in your normal update cycle.
- **Precursor Intelligence risk score:** 48 out of 100 (Medium); action: Plan remediation. Kept up to date as the evidence changes.
- **Severity:** High (CVSS 8.8 out of 10)
- **Known to be exploited:** No, not on the list of flaws known to be exploited today
- **Chance of use in the next 30 days:** 6.0% (latest exploit-likelihood forecast)
- **Published:** 25 July 2017
- **Record last updated:** 20 April 2025
- **Main product:** Webex Meetings Server from Cisco
- **Affected products:** 20

## What is CVE-2017-6753? In plain terms

It can be attacked from anywhere on the internet without logging in, but a person has to take an action first. If it works, the attacker can read data, change data and take it offline.

### The official description

A vulnerability in Cisco WebEx browser extensions for Google Chrome and Mozilla Firefox could allow an unauthenticated, remote attacker to execute arbitrary code with the privileges of the affected browser on an affected system. This vulnerability affects the browser extensions for Cisco WebEx Meetings Server, Cisco WebEx Centers (Meeting Center, Event Center, Training Center, and Support Center), and Cisco WebEx Meetings when they are running on Microsoft Windows. The vulnerability is due to a design defect in the extension. An attacker who can convince an affected user to visit an attacker-controlled web page or follow an attacker-supplied link with an affected browser could exploit the vulnerability. If successful, the attacker could execute arbitrary code with the privileges of the affected browser. The following versions of the Cisco WebEx browser extensions are affected: Versions prior to 1.0.12 of the Cisco WebEx extension on Google Chrome, Versions prior to 1.0.12 of the Cisco WebEx extension on Mozilla Firefox. Cisco Bug IDs: CSCvf15012 CSCvf15020 CSCvf15030 CSCvf15033 CSCvf15036 CSCvf15037.

### What kind of flaw is it?

- CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

### How an attack on it works

- Where an attacker can be: Anywhere on the internet
- How hard it is to pull off: Easy: no special conditions
- Login needed first: No login needed
- Does someone have to click: Yes, a person has to take an action
- What an attacker gets: Can read data, change data and take it offline

Severity vector: `CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`

## Is CVE-2017-6753 being exploited? Not that we know of

It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 6.0%. That can change at any time, which is why we keep watching.

Exploit likelihood over the last 7 days: 6.0%, 6.0%, 6.0%, 6.0%, 6.0%, 6.0%, 6.0%.

### Timeline

- 25 July 2017: Published
- 20 April 2025: Record last updated

### How Precursor Intelligence ranks it

CVE-2017-6753 scores **48 out of 100 (Medium)**, with the action "Plan remediation".

Every published flaw gets a risk score from 0 to 100, kept up to date as the evidence changes. Four things go into the score, from the one that counts most to the ones that count less:

- Evidence it is being exploited: biggest factor
- How severe it is: strong factor
- How widely exposed it is: smaller factor
- Threat activity around it: smaller factor

85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score. When this flaw matches software you track, it lands in your list with its score and the reasons behind it.

## Who is affected by CVE-2017-6753?

The published record lists 20 products.

- [Webex Meetings Server](https://www.precursorintelligence.com/product/cisco/webex_meetings_server) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1.1_base, 1.5_base, 1.5.1.6, 1.5.1.131, 2.0_base, 2.0.1.107, 2.5_base, 2.5.1.5, 2.5.1.29, 2.5.99.2, 2.6.0, 2.6.1.39, 2.7_base, 2.7.1, 2.8_base
- [Webex Meetings Server 2.0](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.0) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): mr2, mr3, mr4, mr5, mr6, mr7, mr8, mr9
- [Webex Meetings Server 2.5](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.5) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): mr1, mr2, mr3, mr4, mr5, mr6
- [Webex Meetings Server 2.5 Mr6 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.5_mr6_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1, 2, 3, 4
- [Webex Event Center](https://www.precursorintelligence.com/product/cisco/webex_event_center) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): t30_base, t31_base, t32_base
- [Webex Meeting Center](https://www.precursorintelligence.com/product/cisco/webex_meeting_center) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): t30_base, t31_base, t32_base
- [Webex Meetings Server 2.0 Mr9 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.0_mr9_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1, 2, 3
- [Webex Meetings Server 2.6](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.6) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): mr1, mr2, mr3
- [Webex Support Center](https://www.precursorintelligence.com/product/cisco/webex_support_center) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): t30_base, t31_base, t32_base
- [Webex Training Center](https://www.precursorintelligence.com/product/cisco/webex_training_center) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): t30_base, t31_base, t32_base
- [Webex Meetings Server 2.6 Mr3 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.6_mr3_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1, 2
- [Webex Meetings Server 2.7](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.7) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): mr1, mr2
- [Webex Meetings](https://www.precursorintelligence.com/product/cisco/webex_meetings) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): t30_base
- [Webex Meetings Server 2.0 Mr8 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.0_mr8_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1
- [Webex Meetings Server 2.5 Mr2 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.5_mr2_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1
- [Webex Meetings Server 2.5 Mr5 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.5_mr5_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1
- [Webex Meetings Server 2.6 Mr1 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.6_mr1_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1
- [Webex Meetings Server 2.6 Mr2 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.6_mr2_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1
- [Webex Meetings Server 2.7 Mr1 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.7_mr1_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1
- [Webex Meetings Server 2.7 Mr2 Patch](https://www.precursorintelligence.com/product/cisco/webex_meetings_server_2.7_mr2_patch) by [Cisco](https://www.precursorintelligence.com/vendors/cisco) (Application): 1

## How do I fix CVE-2017-6753?

1. **Check whether you run it.** Compare your versions with the affected products above. Not sure what you run? Precursor Intelligence can work it out from your public website, or you can pick it from a list.
2. **Apply the vendor’s fix.** Install the update named in the vendor’s advisory. We’ve put the advisory first in the list.
3. **If you can’t patch today.** Follow any mitigation the vendor publishes, and limit who can reach the affected system from the internet until the update is in.
4. **Keep an eye on it.** Track the product and we tell you as soon as we spot this flaw on the list of exploited flaws, or a jump in its exploit likelihood.

### References

- [tools.cisco.com](https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170717-webex) (Vendor advisory)
- [securityfocus.com](http://www.securityfocus.com/bid/99614) (Third-party advisory, Vulnerability database)
- [securitytracker.com](http://www.securitytracker.com/id/1038909) (Third-party advisory, Vulnerability database)
- [securitytracker.com](http://www.securitytracker.com/id/1038910) (Third-party advisory, Vulnerability database)
- [securitytracker.com](http://www.securitytracker.com/id/1038911) (Third-party advisory, Vulnerability database)

## Questions

### What is CVE-2017-6753?

CVE-2017-6753 is a high-severity flaw in Webex Meetings Server from Cisco, published on 25 July 2017. It can be attacked from anywhere on the internet without logging in, but a person has to take an action first. If it works, the attacker can read data, change data and take it offline.

### How serious is CVE-2017-6753?

It scores 8.8 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2017-6753 is 48 out of 100, which is Medium. Its action is "Plan remediation". No sign of exploitation and a low forecast. Patch it in your normal update cycle.

### Is CVE-2017-6753 being exploited?

It is not on the list of flaws known to be exploited today. The latest forecast puts the chance of it being used in the next 30 days at 6.0%. That can change at any time, which is why we keep watching.

### Which versions does CVE-2017-6753 affect?

For Webex Meetings Server from Cisco: 1.1_base, 1.5_base, 1.5.1.6, 1.5.1.131, 2.0_base, 2.0.1.107 and 9 more. The record lists 20 products in all, each with its versions, under "Who is affected" on this page.

### How do I fix CVE-2017-6753?

Install the update the vendor names in its advisory, linked first under "How do I fix" on this page. If you can't patch today, follow the vendor's mitigation and limit who can reach the affected system from the internet.

## Does CVE-2017-6753 affect you?

Precursor Intelligence keeps checking for you:

- **Tell us what you run.** Pick your software from a list, or let us work it out from your website.
- **We match it to every flaw.** Over 400,000 published flaws, checked against your list.
- **Ranked by real-world risk.** Every flaw gets a 0 to 100 risk score, kept up to date, led by evidence criminals are using it.
- **Told as soon as we know.** An alert by email, in the app or by webhook to your own tools.

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