Security readout for executives and security teams
Plain-English summary
CVE-2023-3776 is a Linux kernel local privilege escalation flaw in traffic control filtering. A user who already has local access could potentially gain higher privileges. This is not a remote internet-facing bug, but it matters for shared servers, container hosts, and systems where untrusted users or workloads can run code.
Executive priority
Treat this as a high-priority kernel patching item for systems where local access is possible. It is less urgent than a remotely exploitable internet-facing flaw, but important because successful abuse could convert limited access into full system compromise.
Technical view
The flaw is a use-after-free in net/sched cls_fw. Error handling around tcf_change_indev(), fw_set_parms(), and tcf_bind_filter() can mishandle a reference count, freeing an object still in use. The CVSS 3.1 score is 7.8 with local attack vector, low complexity, low privileges, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most relevant on Linux systems running affected kernels, especially where local shell access, multi-tenant workloads, containers, or untrusted users exist. The bundle lists Linux Kernel and Debian advisories, but does not provide a complete affected-version matrix for every distribution or vendor appliance.
Exploitation context
The supplied sources do not show CISA KEV listing or cited active exploitation. The vulnerability requires local privileges and no user interaction. Its business risk comes from privilege escalation after initial foothold, not direct remote compromise.
Researcher notes
Focus review on cls_fw reference-count handling and vendor backport status. The source bundle gives a clear upstream fix reference and downstream advisories, but incomplete cross-vendor version coverage. Avoid assuming exploit availability or affected distribution versions beyond the cited sources.
Mitigation direction
- Upgrade to a kernel containing or newer than commit 0323bce598eea038714f941ce2b22541c46d488f.
- Apply Debian security updates where Debian advisories apply.
- Check vendor advisories for downstream appliances and supported kernel packages.
- Prioritize shared hosts, container platforms, and systems with untrusted local users.
- Use vendor live patch guidance only where explicitly supported.
Validation and detection
- Inventory Linux kernel versions across servers, appliances, and container hosts.
- Confirm whether deployed kernels include commit 0323bce598eea038714f941ce2b22541c46d488f or vendor backports.
- Check Debian DSA-5480, DSA-5492, and LTS notices for applicable package status.
- Review NetApp advisory applicability for affected products in the environment.
- Record compensating controls only if patching is delayed.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-416: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupPrivilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2023-3776 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=0323bce598eea038714f941ce2b22541c46d488fCVE reference · patch
- https://kernel.dance/0323bce598eea038714f941ce2b22541c46d488fCVE reference
- https://www.debian.org/security/2023/dsa-5480CVE reference
- https://www.debian.org/security/2023/dsa-5492CVE reference
- https://lists.debian.org/debian-lts-announce/2023/10/msg00027.htmlCVE reference
- https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlCVE reference
- https://security.netapp.com/advisory/ntap-20240202-0003/CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.