What is CVE-2020-1677?A high-severity flaw in Mist Cloud UI, explained.

High severity1 affected product
The short answer

CVE-2020-1677 is a high-severity flaw (CVSS 7.2) in Mist Cloud UI from Juniper, published on 16 October 2020. 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 0.4%. If you run an affected version, plan in the vendor’s fix.

Published 16 October 2020. Record last updated 19 October 2021. We keep this page's data up to date.

What it does

What is CVE-2020-1677? In plain terms.

It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can read some data and change some data.

The official description

When SAML authentication is enabled, Juniper Networks Mist Cloud UI might incorrectly handle child elements in SAML responses, allowing a remote attacker to modify a valid SAML response without invalidating its cryptographic signature to bypass SAML authentication security controls. This issue affects all Juniper Networks Mist Cloud UI versions prior to September 2 2020.

What kind of flaw is it?

  • CWE-20Improper Input Validation
  • CWE-345Insufficient Verification of Data Authenticity
CVSS 3.1 scoreHigh · 7.2

How an attack on it works

Read straight from its severity rating, translated out of the shorthand.

  • Where an attacker can beAnywhere on the internet
  • How hard it is to pull offEasy: no special conditions
  • Login needed firstNo login needed
  • Does someone have to clickNo, nobody has to do anything
  • What an attacker getsCan read some data and change some data

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

Exploitation

Is CVE-2020-1677 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 0.4%. That can change at any time, which is why we keep watching.

Known to be exploitedNoNot on the list of exploited flaws today
Chance of use in the next 30 days0.4%Its EPSS score, from the latest forecast

Timeline

  1. Published
  2. Record last updated
How Precursor Intelligence ranks it
46out of 100Medium

CVE-2020-1677 scores 46. Action: Plan remediation.

We keep the score of every published flaw up to date as the evidence changes. Four things go into the score, and evidence that criminals are actually using it counts most. In order:

  • Evidence it is being exploitedBiggest factor
  • How severe it isStrong factor
  • How widely exposed it isSmaller factor
  • Threat activity around itSmaller factor

85 and above is Critical. Anything confirmed as exploited is always marked for an emergency patch, whatever its score.

When CVE-2020-1677 matches software you track, it lands in your list with its score and the reasons behind it.

See your own ranked list →
Affected products

Who is affected by CVE-2020-1677? One product.

The published record lists 1 product from 1 vendor. Versions are shown as published: "before 2020-09-02" means every version up to, but not including, 2020-09-02. If you run one of these, check your version, then go to the fix below.

Remediation

How do I fix CVE-2020-1677? Four steps.

  1. Check whether you run itCompare 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 fixInstall the update named in the vendor’s advisory. We’ve put the advisory first in the list.
  3. If you can’t patch todayFollow 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 itTrack 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

1 link
Precursor Intelligence

Does CVE-2020-1677 affect you? We'll keep checking.

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  1. Tell us what you runPick your software from a list, or let us work it out from your website.
  2. We match it to every flawOver 400,000 published flaws, checked against your list.
  3. Ranked by real-world riskA 0 to 100 score, led by evidence criminals are using it.
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FAQ

Common questions, answered plainly.

Something else? Talk to the team →

CVE-2020-1677 is a high-severity flaw in Mist Cloud UI from Juniper, published on 16 October 2020. It can be attacked from anywhere on the internet without logging in, and nobody has to click anything. If it works, the attacker can read some data and change some data.

It scores 7.2 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2020-1677 is 46 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.

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 0.4%. That can change at any time, which is why we keep watching.

For Mist Cloud UI from Juniper: before 2020-09-02.

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.