Security readout for executives and security teams
Plain-English summary
CVE-2021-35218 affects SolarWinds Patch Manager Web Console. A reachable chart endpoint can mishandle untrusted serialized data and allow remote code execution on the server. The business concern is server compromise in environments where Patch Manager is reachable by an attacker on the network.
Executive priority
Treat as a high-priority remediation item for organizations running SolarWinds Patch Manager. Prioritize systems with broad internal reachability or administrative network placement, because successful exploitation could compromise the management server.
Technical view
The issue is CWE-502 deserialization of untrusted data in the Web Console chart endpoint. The listed affected product is SolarWinds Patch Manager 2020.5 and earlier. CVSS 3.1 is 8.9, with low attack complexity, no user interaction, and high confidentiality and integrity impact.
Likely exposure
Exposure is most likely where SolarWinds Patch Manager Web Console is deployed and reachable from untrusted or broad internal networks. The source bundle does not identify internet-scale exposure, specific ports, or cloud-hosted variants.
Exploitation context
The source bundle does not show CISA KEV listing or cited evidence of active exploitation. It does indicate potential remote code execution by an attacker with network access to the Orion Patch Manager Web Console.
Researcher notes
Evidence is limited to the CVE record, SolarWinds references, and ZDI advisory. There is a CVSS inconsistency to note: the vector indicates adjacent network and low privileges, while the description says unauthorized attacker with network access.
Mitigation direction
- Identify all SolarWinds Patch Manager deployments and versions.
- Follow SolarWinds advisory and release notes for the vendor-supported fixed release.
- Restrict Web Console access to trusted administrative networks only.
- Apply least-privilege access controls for Patch Manager administration.
- Monitor Patch Manager servers for unexpected process activity or configuration changes.
Validation and detection
- Confirm whether Patch Manager version is 2020.5 or earlier.
- Verify the Web Console is not reachable from untrusted networks.
- Review SolarWinds advisory status for the installed build.
- Check access logs for unusual Web Console requests around disclosure and afterward.
- Confirm compensating network controls are enforced at firewalls or access gateways.
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-502: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-35218 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
- 8.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L
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:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L2.36Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.9HighVector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L
Source materials
- CVE List V5 sourceCVE List V5
- https://documentation.solarwinds.com/en/success_center/patchman/content/release_notes/patchman_2020-2-6_release_notes.htmCVE reference · x_refsource_MISC
- https://www.solarwinds.com/trust-center/security-advisories/cve-2021-35218CVE reference · x_refsource_MISC
- https://www.zerodayinitiative.com/advisories/ZDI-21-1248/CVE 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.
Deserialization of Untrusted Data
Deserialization of Untrusted Data represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.