Every CVE Search/ Get API key

CVE-2023-3326

Network authentication attack via pam_krb5

9.8 Critical

pam_krb5 authenticates a user by essentially running kinit with the password, getting a ticket-granting ticket (tgt) from the Kerberos KDC (Key Distribution Center) over the network, as a way to verify the password. However, if a keytab is not provisioned on the system, pam_krb5 has no way to validate the response from the KDC, and essentially trusts the tgt provided over the network as being valid. In a non-default FreeBSD installation that leverages pam_krb5 for authentication and does not have a keytab provisioned, an attacker that is able to control both the password and the KDC responses can return a valid tgt, allowing authentication to occur for any user on the system.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
Low
Privileges needed
None
User interaction
None

What an attacker can affect

Confidentiality
High
Integrity
High
Availability
High

Exploit likelihood

1.10%Up 1.1 points since Jun 23, 2023
90%50%10%1%

What each source reports

NVD Score used 9.8

pam_krb5 authenticates a user by essentially running kinit with the password, getting a ticket-granting ticket (tgt) from the Kerberos KDC (Key Distribution Center) over the network, as a way to verify the password. However, if a keytab is not provisioned on the system, pam_krb5 has no way to validate the response from the KDC, and essentially trusts the tgt provided over the network as being valid. In a non-default FreeBSD installation that leverages pam_krb5 for authentication and does not have a keytab provisioned, an attacker that is able to control both the password and the KDC responses can return a valid tgt, allowing authentication to occur for any user on the system.

Record
CVE-2023-3326
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
CWE-303, CWE-287
Updated
2026-11-02
CVE List No score

Network authentication attack via pam_krb5

pam_krb5 authenticates a user by essentially running kinit with the password, getting a ticket-granting ticket (tgt) from the Kerberos KDC (Key Distribution Center) over the network, as a way to verify the password. However, if a keytab is not provisioned on the system, pam_krb5 has no way to validate the response from the KDC, and essentially trusts the tgt provided over the network as being valid. In a non-default FreeBSD installation that leverages pam_krb5 for authentication and does not have a keytab provisioned, an attacker that is able to control both the password and the KDC responses can return a valid tgt, allowing authentication to occur for any user on the system.

Record
CVE-2023-3326
Weakness
CWE-303
Updated
2026-11-02
EUVDEUVD-2023-43994 0.0

pam_krb5 authenticates a user by essentially running kinit with the password, getting a ticket-granting ticket (tgt) from the Kerberos KDC (Key Distribution Center) over the network, as a way to verify the password. However, if a keytab is not provisioned on the system, pam_krb5 has no way to validate the response from the KDC, and essentially trusts the tgt provided over the network as being valid. In a non-default FreeBSD installation that leverages pam_krb5 for authentication and does not have a keytab provisioned, an attacker that is able to control both the password and the KDC responses can return a valid tgt, allowing authentication to occur for any user on the system.

Record
EUVD-2023-43994
CVSS
0.0 NoneCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated
2026-11-03
GitHub AdvisoriesGHSA-vjhp-527w-c5vj 9.8

pam_krb5 authenticates a user by essentially running kinit with the password, getting a ticket...

pam_krb5 authenticates a user by essentially running kinit with the password, getting a ticket-granting ticket (tgt) from the Kerberos KDC (Key Distribution Center) over the network, as a way to verify the password. However, if a keytab is not provisioned on the system, pam_krb5 has no way to validate the response from the KDC, and essentially trusts the tgt provided over the network as being valid. In a non-default FreeBSD installation that leverages pam_krb5 for authentication and does not have a keytab provisioned, an attacker that is able to control both the password and the KDC responses can return a valid tgt, allowing authentication to occur for any user on the system.

Record
GHSA-vjhp-527w-c5vj
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness
CWE-287, CWE-303
Updated
2026-11-02
OSV 9.8

pam_krb5 authenticates a user by essentially running kinit with the password, getting a ticket-granting ticket (tgt) from the Kerberos KDC (Key Distribution Center) over the network, as a way to verify the password. However, if a keytab is not provisioned on the system, pam_krb5 has no way to validate the response from the KDC, and essentially trusts the tgt provided over the network as being valid. In a non-default FreeBSD installation that leverages pam_krb5 for authentication and does not have a keytab provisioned, an attacker that is able to control both the password and the KDC responses can return a valid tgt, allowing authentication to occur for any user on the system.

Record
CVE-2023-3326
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated
2026-11-02
OSVDEBIAN-CVE-2023-3326 9.8

pam_krb5 authenticates a user by essentially running kinit with the password, getting a ticket-granting ticket (tgt) from the Kerberos KDC (Key Distribution Center) over the network, as a way to verify the password. However, if a keytab is not provisioned on the system, pam_krb5 has no way to validate the response from the KDC, and essentially trusts the tgt provided over the network as being valid. In a non-default FreeBSD installation that leverages pam_krb5 for authentication and does not have a keytab provisioned, an attacker that is able to control both the password and the KDC responses can return a valid tgt, allowing authentication to occur for any user on the system.

Record
DEBIAN-CVE-2023-3326
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated
2026-11-02
OSVUBUNTU-CVE-2023-3326 9.8

pam_krb5 authenticates a user by essentially running kinit with the password, getting a ticket-granting ticket (tgt) from the Kerberos KDC (Key Distribution Center) over the network, as a way to verify the password. However, if a keytab is not provisioned on the system, pam_krb5 has no way to validate the response from the KDC, and essentially trusts the tgt provided over the network as being valid. In a non-default FreeBSD installation that leverages pam_krb5 for authentication and does not have a keytab provisioned, an attacker that is able to control both the password and the KDC responses can return a valid tgt, allowing authentication to occur for any user on the system.

Record
UBUNTU-CVE-2023-3326
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated
2026-11-02

Affected products

Affected packages

Affected packages
PackageAffectedFixed
libpam-krb5
Debian:12
All versions, plus listed versions
4.11-14.11-1.14.11-2
None known
libpam-krb5
Debian:13
All versions, plus listed versions
4.11-2
None known
libpam-krb5
Debian:14
All versions, plus listed versions
4.11-2
None known
libpam-krb5
Ubuntu:Pro:14.04:LTS
All versions, plus listed versions
4.6-24.6-2ubuntu0.1~esm1
None known
libpam-krb5
Ubuntu:16.04:LTS
All versions, plus listed versions
4.7-24.7-2ubuntu0.1
None known
sssd
Ubuntu:Pro:16.04:LTS
All versions, plus listed versions
1.12.5-21.13.1-21.13.2-11.13.3-11.13.4-1
Show 15 moreShow less
1.13.4-1ubuntu11.13.4-1ubuntu1.11.13.4-1ubuntu1.21.13.4-1ubuntu1.51.13.4-1ubuntu1.61.13.4-1ubuntu1.71.13.4-1ubuntu1.81.13.4-1ubuntu1.91.13.4-1ubuntu1.101.13.4-1ubuntu1.111.13.4-1ubuntu1.121.13.4-1ubuntu1.131.13.4-1ubuntu1.141.13.4-1ubuntu1.151.13.4-1ubuntu1.15+esm1
None known
libpam-krb5
Ubuntu:18.04:LTS
All versions, plus listed versions
4.7-44.8-14.8-1ubuntu0.1
None known
sssd
Ubuntu:Pro:18.04:LTS
All versions, plus listed versions
1.15.3-2ubuntu11.15.3-3ubuntu11.16.0-5ubuntu11.16.0-5ubuntu21.16.1-1ubuntu1
Show 9 moreShow less
1.16.1-1ubuntu1.11.16.1-1ubuntu1.21.16.1-1ubuntu1.31.16.1-1ubuntu1.41.16.1-1ubuntu1.51.16.1-1ubuntu1.61.16.1-1ubuntu1.71.16.1-1ubuntu1.81.16.1-1ubuntu1.8+esm1
None known
libpam-krb5
Ubuntu:20.04:LTS
All versions, plus listed versions
4.8-24.8-2ubuntu1
None known
sssd
Ubuntu:Pro:20.04:LTS
All versions, plus listed versions
2.2.0-4ubuntu12.2.2-12.2.2-1ubuntu12.2.3-1.1ubuntu12.2.3-2
Show 14 moreShow less
2.2.3-32.2.3-3ubuntu0.12.2.3-3ubuntu0.22.2.3-3ubuntu0.32.2.3-3ubuntu0.42.2.3-3ubuntu0.62.2.3-3ubuntu0.72.2.3-3ubuntu0.82.2.3-3ubuntu0.92.2.3-3ubuntu0.102.2.3-3ubuntu0.112.2.3-3ubuntu0.122.2.3-3ubuntu0.132.2.3-3ubuntu0.13+esm1
None known
Show 10 moreShow less
Affected packages
PackageAffectedFixed
libpam-krb5
Ubuntu:22.04:LTS
All versions, plus listed versions
4.9-2build14.11-14.11-1build1
None known
sssd
Ubuntu:22.04:LTS
All versions, plus listed versions
2.4.1-2ubuntu42.5.2-4ubuntu12.5.2-4ubuntu32.5.2-4ubuntu42.6.1-1ubuntu3
Show 9 moreShow less
2.6.3-1ubuntu32.6.3-1ubuntu3.12.6.3-1ubuntu3.22.6.3-1ubuntu3.32.6.3-1ubuntu3.42.6.3-1ubuntu3.52.6.3-1ubuntu3.62.6.3-1ubuntu3.82.6.3-1ubuntu3.9
None known
libpam-krb5
Ubuntu:24.04:LTS
All versions, plus listed versions
4.11-1build14.11-1build24.11-1build3
None known
sssd
Ubuntu:24.04:LTS
All versions, plus listed versions
2.9.1-2ubuntu22.9.1-2ubuntu32.9.2-1ubuntu22.9.4-1ubuntu12.9.4-1.1ubuntu3
Show 10 moreShow less
2.9.4-1.1ubuntu52.9.4-1.1ubuntu62.9.4-1.1ubuntu6.12.9.4-1.1ubuntu6.22.9.4-1.1ubuntu6.32.9.4-1.1ubuntu6.42.9.4-1.1ubuntu6.52.9.4-1.1ubuntu6.62.9.4-1.1ubuntu6.72.9.4-1.1ubuntu6.8
None known
libpam-krb5
Ubuntu:25.10
All versions, plus listed versions
4.11-2
None known
sssd
Ubuntu:25.10
All versions, plus listed versions
2.10.1-2ubuntu42.10.1-2ubuntu52.10.1-2ubuntu5.12.10.1-2ubuntu5.22.10.1-2ubuntu5.3
None known
libpam-krb5
Ubuntu:26.10
All versions, plus listed versions
4.11-2build1
None known
sssd
Ubuntu:26.10
All versions, plus listed versions
2.12.0-1ubuntu52.12.0-4ubuntu12.12.0-4ubuntu22.12.0-4ubuntu32.12.0-4ubuntu4
None known
libpam-krb5
Ubuntu:26.04:LTS
All versions, plus listed versions
4.11-24.11-2build1
None known
sssd
Ubuntu:26.04:LTS
All versions, plus listed versions
2.10.1-2ubuntu52.10.1-2ubuntu72.12.0-1ubuntu32.12.0-1ubuntu42.12.0-1ubuntu5
Show 5 moreShow less
2.12.0-1ubuntu5.12.12.0-1ubuntu5.22.12.0-1ubuntu5.32.12.0-1ubuntu5.42.12.0-1ubuntu5.5
None known

History

History
RecordedChangedSources
aliases, publishedEUVD
first indexedCVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2023-3326 is a critical vulnerability (CVSS 9.8) in Freebsd, published June 22, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.10%, the 65th percentile. No source names a fixed version.

References

MoveEnter Open