CVE-2021-3738
No known exploitation. EPSS puts it in the 80th percentile. A vendor fix is available.
What to do
The vendor has published a fix. Version details are below where the sources state them.
What it is
From the CVE record
In DCE/RPC it is possible to share the handles (cookies for resource state) between multiple connections via a mechanism called 'association groups'. These handles can reference connections to our sam.ldb database. However while the database was correctly shared, the user credentials state was only pointed at, and when one connection within that association group ended, the database would be left pointing at an invalid 'struct session_info'. The most likely outcome here is a crash, but it is possible that the use-after-free could instead allow different user state to be pointed at and this might allow more privileged access.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
2.0% chance of exploitation activity in the next 30 days, which ranks it in the 80th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
6 events over 1576 days, from the signal feeds we watch.
- OpenVAS check added
- Patch availablerecord updated
- Publishedweakness classified, att&ck mapped
Affected products
- SUSE Linux Enterprise High AvailabilityOperating Systems / linux-distro
- openSUSE TumbleweedOperating Systems / linux-distro
- SUSE Linux Enterprise Module for Open Buildservice Development ToolsOperating Systems / linux-distro
- SUSE Linux Enterprise Module for BasesystemOperating Systems / linux-distro
- OpenSUSE LeapOperating Systems / linux-distro
- SUSE Linux Enterprise Module for Python2 packagesOperating Systems / linux-distro
- SUSE MicroOSOperating Systems / linux-distro
And 2 more affected products. See all after sign-in
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Scored 8.8 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity LowNo special conditions — the attack can be reliably reproduced
- Privileges Required LowRequires basic user-level privileges
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity HighTotal loss of integrity — attacker can modify any data in the component
- Availability HighTotal denial of service — the component is completely unavailable
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
- Initial AccessT1190Exploit Public-Facing Applicationhigh confidence
- Privilege EscalationT1068Exploitation for Privilege Escalationhigh confidence
Sources
References in the record
- samba.org/samba/security/CVE-2021-3738.html
- bugzilla.samba.org/show_bug.cgi?id=14468
- bugzilla.redhat.com/show_bug.cgi?id=2021726
And 10 more references. See all after sign-in
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