Security readout for executives and security teams
Plain-English summary
Exim versions before 4.94.2 mishandled log-directory privileges. Because Exim acted as root in a directory owned by a non-root user, an attacker could use filesystem links to overwrite root-owned files. That can create serious host integrity risk, but the provided sources do not show active exploitation.
Executive priority
Prioritize remediation on production mail servers, especially shared or multi-user systems. The business risk is host compromise through root-owned file overwrite, but urgency should be based on confirmed Exim version, local access exposure, and vendor patch availability.
Technical view
CVE-2020-28007 is an Execution with Unnecessary Privileges flaw in Exim 4 before 4.94.2. The described condition enables symlink or hard-link abuse from the log directory context, allowing overwrite of critical root-owned files elsewhere on the filesystem. No CVSS, CWE, or detailed affected CPE data is provided in the bundle.
Likely exposure
Systems running Exim 4 earlier than 4.94.2 are potentially exposed. The strongest concern is mail infrastructure where untrusted local users or processes can influence filesystem links in the relevant log-directory context. The bundle does not identify specific distributions, packages, or CPEs.
Exploitation context
The source bundle does not cite CISA KEV and does not provide evidence of active exploitation. The described attack path is filesystem-based privilege misuse rather than a confirmed remote exploitation campaign. Treat exploitability assumptions cautiously without vendor or distribution-specific advisories.
Researcher notes
Evidence is limited to the CVE record and Exim security reference. The bundle lacks CVSS, CWE mapping, affected CPEs, exploit telemetry, and distribution-specific fixes. Avoid asserting remote exploitability or active exploitation without additional primary sources.
Mitigation direction
- Upgrade Exim to 4.94.2 or later where applicable.
- Check vendor or distribution advisories for patched package versions.
- Restrict untrusted local access to affected mail hosts.
- Review log-directory ownership and permissions against vendor guidance.
- Prioritize hosts that process production email or have local user access.
Validation and detection
- Inventory Exim versions across mail servers and appliances.
- Confirm no host runs Exim 4 earlier than 4.94.2.
- Verify patched package status through OS package metadata.
- Review log-directory ownership and permissions on Exim hosts.
- Check change records for vendor advisory coverage.
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.
CVE-2020-28007 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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 and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://www.exim.org/static/doc/security/CVE-2020-qualys/CVE-2020-28007-LFDIR.txtCVE reference · x_refsource_MISC
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.