What is CVE-2021-25321?A high-severity flaw in Arpwatch, explained.
CVE-2021-25321 is a high-severity flaw (CVSS 7.8) in Arpwatch from Suse, published on 30 June 2021. 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 30 June 2021. Record last updated 22 June 2023. We keep this page's data up to date.
What is CVE-2021-25321? In plain terms.
An attacker has to be already on the device with an ordinary user account, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline.
A UNIX Symbolic Link (Symlink) Following vulnerability in arpwatch of SUSE Linux Enterprise Server 11-SP4-LTSS, SUSE Manager Server 4.0, SUSE OpenStack Cloud Crowbar 9; openSUSE Factory, Leap 15.2 allows local attackers with control of the runtime user to run arpwatch as to escalate to root upon the next restart of arpwatch. This issue affects: SUSE Linux Enterprise Server 11-SP4-LTSS arpwatch versions prior to 2.1a15. SUSE Manager Server 4.0 arpwatch versions prior to 2.1a15. SUSE OpenStack Cloud Crowbar 9 arpwatch versions prior to 2.1a15. openSUSE Factory arpwatch version 2.1a15-169.5 and prior versions. openSUSE Leap 15.2 arpwatch version 2.1a15-lp152.5.5 and prior versions.
What kind of flaw is it?
- CWE-61UNIX Symbolic Link (Symlink) Following
How an attack on it works
Read straight from its severity rating, translated out of the shorthand.
- Where an attacker can beAlready on the device
- How hard it is to pull offEasy: no special conditions
- Login needed firstAn ordinary user account
- Does someone have to clickNo, nobody has to do anything
- What an attacker getsCan read data, change data and take it offline
Severity vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is CVE-2021-25321 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.
Timeline
- Published
- Record last updated
CVE-2021-25321 scores 49. 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-2021-25321 matches software you track, it lands in your list with its score and the reasons behind it.
See your own ranked list →Who is affected by CVE-2021-25321? 6 products.
The published record lists 6 products from 2 vendors. Versions are shown as published: "before 2.1a15" means every version up to, but not including, 2.1a15. If you run one of these, check your version, then go to the fix below.
- Application
Arpwatch
by Suse
Affected versionsbefore 2.1a15up to 2.1a15-169.5up to 2.1a15-lp152.5.5 - Application
Factory
by Opensuse
Affected versionsversion not specified - Operating system
Leap
by Opensuse
Affected versions15.2 - Operating system
Linux Enterprise Server
by Suse
Affected versions11-sp4 - Application
Manager Server
by Suse
Affected versions4.0 - Application
Openstack Cloud Crowbar
by Suse
Affected versions9.0
How do I fix CVE-2021-25321? Four steps.
- 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.
- Apply the vendor’s fixInstall the update named in the vendor’s advisory. We’ve put the advisory first in the list.
- 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.
- 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 linkDoes CVE-2021-25321 affect you? We'll keep checking.
Looking flaws up one at a time doesn't scale. Tell us what you run once, and we tell you which flaws matter to you, in what order, and keep watching for new ones.
- Tell us what you runPick your software from a list, or let us work it out from your website.
- We match it to every flawOver 400,000 published flaws, checked against your list.
- Ranked by real-world riskA 0 to 100 score, led by evidence criminals are using it.
- Told as soon as we knowAn alert by email, in the app or by webhook to your own tools.
Free plan, no card needed. Nothing to install.
1 new flaw affects software Acme tracks
A UNIX Symbolic Link (Symlink) Following vulnerability in arpwatch of SUSE Linux Enterprise Server 11-SP4-LTSS, SUSE Manager Server 4.0, SUSE OpenStack Cloud...
- Matched to
- Arpwatch on Acme's software list
- What to do
- Plan in the vendor’s update
Sent to the alert recipients Acme chose. Also in the app and to Acme's webhook.
CVE-2021-25321 is a high-severity flaw in Arpwatch from Suse, published on 30 June 2021. An attacker has to be already on the device with an ordinary user account, and nobody has to click anything. If it works, the attacker can read data, change data and take it offline.
It scores 7.8 out of 10 on the CVSS severity scale, which is high. Our risk score for CVE-2021-25321 is 49 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 Arpwatch from Suse: before 2.1a15, up to 2.1a15-169.5, up to 2.1a15-lp152.5.5. The record lists 6 products in all, each with its versions, under "Who is affected" on this page.
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.