Security readout for executives and security teams
Plain-English summary
A crafted ARJ archive can crash vulnerable ClamAV scanning, interrupting malware inspection on systems that process untrusted files, emails, uploads, or archives. The issue affects availability, not confidentiality or integrity, but scanning outages can disrupt mail gateways, file intake, and security workflows.
Executive priority
Prioritize patching on internet-facing upload paths, mail gateways, and shared-file scanning points. This is not a data-theft issue in the supplied sources, but it can disable a security control that other business processes depend on.
Technical view
CVE-2020-3327 is a heap buffer overflow read in ClamAV 0.102.2's ARJ archive parser. Remote unauthenticated input can trigger a ClamAV scanning process crash, causing denial of service. The CVSS 3.1 score is 7.5 with high availability impact.
Likely exposure
Exposure is most likely where ClamAV scans untrusted archives, email attachments, uploads, or file shares. The bundle identifies ClamAV 0.102.2 and downstream Linux security updates, but does not provide a complete affected-version matrix.
Exploitation context
The source bundle describes remote unauthenticated exploitation through a crafted ARJ file. It does not cite public exploitation or CISA KEV listing, and KEV is marked false. Treat exploitation as plausible but not confirmed active from these sources.
Researcher notes
The key primitive is an out-of-bounds heap read in ARJ parsing leading to scanner crash. Sources provide CVSS, attack preconditions, and vendor update references, but not detailed affected-version ranges beyond ClamAV 0.102.2 or proof of active exploitation.
Mitigation direction
- Update ClamAV to 0.102.3 or a supported vendor security package.
- Apply relevant Debian, Fedora, Ubuntu, or Gentoo package advisories where applicable.
- Ensure services restart after package updates so scanners run patched binaries.
- If immediate patching is delayed, review vendor guidance for temporary risk reduction.
Validation and detection
- Inventory systems running ClamAV and identify version 0.102.2 deployments.
- Confirm package updates match the vendor advisory for each operating system.
- Review mail, upload, and file-scanning services for ClamAV crash or restart events.
- Verify archive scanning remains available after patching and service restart.
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-20: 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 lookupCVE-2020-3327 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
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://blog.clamav.net/2020/05/clamav-01023-security-patch-released.htmlCVE reference · vendor-advisory, x_refsource_CISCO
- [debian-lts-announce] 20200519 [SECURITY] [DLA 2215-1] clamav security updateCVE reference · mailing-list, x_refsource_MLIST
- FEDORA-2020-bca44487a1CVE reference · vendor-advisory, x_refsource_FEDORA
- FEDORA-2020-d98d2cbae1CVE reference · vendor-advisory, x_refsource_FEDORA
- FEDORA-2020-b0acd7b66eCVE reference · vendor-advisory, x_refsource_FEDORA
- USN-4370-1CVE reference · vendor-advisory, x_refsource_UBUNTU
- USN-4370-2CVE reference · vendor-advisory, x_refsource_UBUNTU
- GLSA-202007-23CVE reference · vendor-advisory, x_refsource_GENTOO
- USN-4435-1CVE reference · vendor-advisory, x_refsource_UBUNTU
- FEDORA-2020-dd0c20d985CVE reference · vendor-advisory, x_refsource_FEDORA
- USN-4435-2CVE reference · vendor-advisory, x_refsource_UBUNTU
- FEDORA-2020-6584a641aeCVE reference · vendor-advisory, x_refsource_FEDORA
- [debian-lts-announce] 20200806 [SECURITY] [DLA 2314-1] clamav security updateCVE reference · mailing-list, x_refsource_MLIST
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.
Improper Input Validation
Improper Input Validation represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.