Security readout for executives and security teams
Plain-English summary
This CVE affects Exim mail servers before version 4.94.2. A malformed sender-name option can trigger an off-by-two out-of-bounds write. The bundle does not provide CVSS, exploitability, or impact details, so urgency should be based on whether vulnerable Exim versions are present.
Executive priority
Treat as an exposure-verification task for mail infrastructure. Escalate if older Exim versions are found, but avoid claims of active exploitation from the supplied evidence.
Technical view
Exim before 4.94.2 mishandles an empty `-F` sender-name value in `parse_fix_phrase`, causing an off-by-two out-of-bounds write. The source bundle does not state privilege requirements, remote reachability, successful exploitation impact, or affected platform constraints.
Likely exposure
Potential exposure exists on systems running Exim versions earlier than 4.94.2. The provided affected-product metadata is incomplete, so validate installed Exim packages directly rather than relying on CPE matching.
Exploitation context
The CVE is not listed as KEV in the bundle, and no cited source states active exploitation. The available evidence identifies the bug condition but does not establish weaponized exploitation or real-world abuse.
Researcher notes
The key technical signal is an off-by-two out-of-bounds write in `parse_fix_phrase` when handling an empty `-F` value. The bundle lacks CVSS, CWE, exploit prerequisites, and impact detail, limiting confidence in severity classification.
Mitigation direction
- Upgrade Exim to 4.94.2 or later where applicable.
- Use vendor or OS distribution advisories for supported package fixes.
- Prioritize internet-facing or business-critical mail infrastructure.
- Document any temporary risk acceptance for unsupported Exim deployments.
Validation and detection
- Inventory all systems running Exim and record exact versions.
- Confirm no deployed Exim version is earlier than 4.94.2.
- Review package-manager advisory status for patched backports.
- Check mail infrastructure inventories for unmanaged Exim instances.
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-2020-28016 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-2020-28016-PFPZA.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.