Cyber Resilience

CVE-2021-3738

High

Published: 02 March 2022

Published
02 March 2022
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0040 61.2th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-3738 is a high-severity Use After Free (CWE-416) vulnerability in Samba Samba. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 38.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

samba
samba
4.0.0 — 4.13.14 · 4.14.0 — 4.14.10 · 4.15.0 — 4.15.2

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

References