Analyst readout for executives and security teams
Plain-English summary
ArcReader can read past intended memory when opening a malicious PMF file. The likely impact is limited information disclosure from the current user's process, not system takeover. It matters where staff exchange map files with outside parties, because exploitation depends on convincing someone to open a crafted file.
Executive priority
Treat this as a low-priority patch hygiene issue unless ArcReader is widely used with external PMF files. Prioritize inventory and vendor-guided remediation over emergency response.
Technical view
CVE-2021-29118 is a CWE-125 out-of-bounds read in Esri ArcReader PMF parsing. The CVSS vector is local, low complexity, no privileges, user interaction required, unchanged scope, and low confidentiality impact. The bundle names ArcReader 10.8.1 and earlier, while its affected list says all ArcReader versions.
Likely exposure
Exposure is most likely on desktops or shared workstations where Esri ArcReader is installed and users open PMF files received from email, portals, vendors, or partners.
Exploitation context
The source bundle does not identify active exploitation, and the CVE is not listed as KEV. Attack requires user interaction with a specially crafted file and results in information disclosure in the current user's context.
Researcher notes
Evidence supports local, user-assisted file parsing exposure with confidentiality-only impact. Patch details are not present in the provided bundle beyond the Esri advisory reference, so remediation should be verified directly against vendor guidance.
Mitigation direction
- Review Esri's ArcReader security update guidance for the vendor-supported fix.
- Inventory ArcReader installations, especially version 10.8.1 and earlier.
- Limit opening PMF files from untrusted or unexpected sources.
- Remove ArcReader where there is no active business requirement.
- Route external PMF files through existing security review workflows.
Validation and detection
- Confirm whether ArcReader is installed on managed endpoints.
- Record installed versions and compare them with Esri guidance.
- Check whether the relevant Esri security update has been applied.
- Review business workflows that accept PMF files from external parties.
- Look for security alerts tied to suspicious PMF attachments or downloads.
Public sources used
Based on public source material and reviewed before publication.
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-125: Exact CWE lookup
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Open ATT&CK lookupCVE-2021-29118 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
- Low
- CVSS
- 3.3 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
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:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N1.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
3.3LowVector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.esri.com/arcgis-blog/products/arcgis-desktop/administration/arcreader-general-data-frame-security-update/CVE reference · x_refsource_CONFIRM
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.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.