What is CVE-2011-4862?A critical-severity flaw in Inetutils, explained.
CVE-2011-4862 is a critical-severity flaw (CVSS 10.0) in Inetutils from Gnu, published on 25 December 2011. 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 95%. If you run an affected version, plan in the vendor’s fix.
Published 25 December 2011. Record last updated 16 June 2026. We keep this page's data up to date.
What is CVE-2011-4862? In plain terms.
It can be attacked from anywhere on the internet without logging in. If it works, the attacker can read data, change data and take it offline.
Buffer overflow in libtelnet/encrypt.c in telnetd in FreeBSD 7.3 through 9.0, MIT Kerberos Version 5 Applications (aka krb5-appl) 1.0.2 and earlier, Heimdal 1.5.1 and earlier, GNU inetutils, and possibly other products allows remote attackers to execute arbitrary code via a long encryption key, as exploited in the wild in December 2011.
What kind of flaw is it?
- CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
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
- What an attacker getsCan read data, change data and take it offline
Severity vector: AV:N/AC:L/Au:N/C:C/I:C/A:C
Is CVE-2011-4862 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 95%. That can change at any time, which is why we keep watching.
Timeline
- Published
- Record last updated
CVE-2011-4862 scores 74. Action: Patch now.
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-2011-4862 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-2011-4862? 10 products.
The published record lists 10 products from 8 vendors. Versions are shown as published: "before 1.9" means every version up to, but not including, 1.9. If you run one of these, check your version, then go to the fix below.
- Application
Inetutils
by Gnu
Affected versionsbefore 1.9 - Operating system
Linux Enterprise Server
by Suse
Affected versions910-sp210-sp310-sp411-sp1 - Operating system
Debian Linux
by Debian
Affected versions5.06.07.0 - Operating system
Fedora
Affected versions1516 - Operating system
Linux Enterprise Desktop
by Suse
Affected versions10-sp411-sp1 - Operating system
Linux Enterprise Software Development Kit
by Suse
Affected versions10-sp411-sp1 - Operating system
Opensuse
by Opensuse
Affected versions11.311.4 - Operating system
FreeBSD
by FreeBSD
Affected versions7.3 to 9.0 - Application
Heimdal
Affected versionsup to 1.5.1
How do I fix CVE-2011-4862? 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 advisories and patch notes 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.
Does CVE-2011-4862 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
Buffer overflow in libtelnet/encrypt.c in telnetd in FreeBSD 7.3 through 9.0, MIT Kerberos Version 5 Applications (aka krb5-appl) 1.0.2 and earlier, Heimdal ...
- Matched to
- Inetutils 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-2011-4862 is a critical-severity flaw in Inetutils from Gnu, published on 25 December 2011. It can be attacked from anywhere on the internet without logging in. If it works, the attacker can read data, change data and take it offline.
It scores 10.0 out of 10 on the CVSS severity scale, which is critical. Our risk score for CVE-2011-4862 is 74 out of 100, which is High. Its action is "Patch now". Not confirmed as exploited yet, but serious or likely enough that it should not wait for a quiet month.
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 95%. That can change at any time, which is why we keep watching.
For Inetutils from Gnu: before 1.9. The record lists 10 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.