CVE-2011-4091: The libobby server in inc/server.hpp in libnet6 (aka net6) before 1.3.14 does not perform authentication befor

Q: How do I fix CVE-2011-4091?

opensuse: mitigate or apply the listed mitigation; solaris: mitigate or apply the listed mitigation; net6: upgrade to newer than 1.3.13. Exact commands for each OS are on this page.

Q: Is CVE-2011-4091 being exploited?

CVE-2011-4091 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2011-4091 affect?

CVE-2011-4091 affects opensuse, solaris, net6. Severity is medium (CVSS 5.0). The libobby server in inc/server.hpp in libnet6 (aka net6) before 1.3.14 does not perform authentication before checking the user name, which allows remote attackers to obtain sensitive information such as server-usage patterns by a particu

Q: How urgent is CVE-2011-4091?

Priority 39/100. No elevated risk signals yet.

Routine

MEDIUM 5.0MITIGATEMITIGATEUPGRADE

CVE-2011-4091 is a medium-severity flaw (CVSS 5.0) affecting opensuse, solaris, net6. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The libobby server in inc/server.hpp in libnet6 (aka net6) before 1.3.14 does not perform authentication before checking the user name, which allows remote attackers to obtain sensitive information such as server-usage patterns by a particular user and color preferences.

Why this priority

No elevated risk signals yet

A fixed release or distro patch exists.

Risk facts

CVSS score	5.0 (Medium)
EPSS exploit chance	2.7% (top 14%)
CISA exploited list	No
Weakness	CWE-287
Published	2014-02-10
Last modified	2026-06-16

Publisher (CNA): Red Hat, Inc. · Vendor: armin burgmeier · opensuse · oracle

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2014-02-10 18:15 UTCPublished CVE record published
2026-06-16 23:34 UTCUpdated Record last modified

opensuse opensuse MITIGATE

Affected: 11.3 · 11.4

Fixed in: no fixed release known

Safe to downgrade to: a release before 11.3

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

oracle solaris MITIGATE

Affected: 11.2

Fixed in: no fixed release known

Safe to downgrade to: a release before 11.2

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

armin burgmeier net6 UPGRADE

Affected: <= 1.3.13 · 1.3.1 · 1.3.2 · 1.3.3 · 1.3.4 · 1.3.5 · 1.3.6 · 1.3.7

Fixed in: newer than 1.3.13

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy net6 || rpm -q net6 || net6 --version

2. UPGRADE to newer than 1.3.13 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade net6

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade net6

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2011-4091?

opensuse: mitigate or apply the listed mitigation; solaris: mitigate or apply the listed mitigation; net6: upgrade to newer than 1.3.13. Exact commands for each OS are on this page.

Is CVE-2011-4091 being exploited?

CVE-2011-4091 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2011-4091 affect?

CVE-2011-4091 affects opensuse, solaris, net6. Severity is medium (CVSS 5.0). The libobby server in inc/server.hpp in libnet6 (aka net6) before 1.3.14 does not perform authentication before checking the user name, which allows remote attackers to obtain sensitive information such as server-usage patterns by a particu

How urgent is CVE-2011-4091?

Priority 39/100. No elevated risk signals yet.

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References

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