Security readout for executives and security teams
Plain-English summary
PyWPS before 4.4.5 had an XML parsing flaw that could let an attacker read files from the application server. That can expose secrets if PyWPS is reachable and runs with access to sensitive files. Public sources do not provide CVSS scoring or active exploitation evidence.
Executive priority
Treat this as a confidentiality risk for systems running vulnerable PyWPS. Prioritize internet-exposed deployments and servers with access to credentials, keys, or sensitive data. Urgency is lower than a confirmed exploited vulnerability but patching should not wait.
Technical view
CVE-2021-39371 is an XXE issue in PyWPS before 4.4.5. The CVE states an attacker could view files on the server filesystem by assigning a path to an XML entity. OWSLib 0.24.1 is listed as possibly affected, but the source bundle does not confirm scope or remediation for OWSLib.
Likely exposure
Organizations running PyWPS versions earlier than 4.4.5, especially internet-reachable WPS/OWS services that parse XML input, are the clearest exposure. OWSLib 0.24.1 exposure is uncertain in the provided sources.
Exploitation context
The source bundle does not show CISA KEV listing or cited evidence of active exploitation. The described impact is unauthorized server-side file disclosure through XXE, not confirmed remote code execution.
Researcher notes
Evidence is limited to the CVE description, PyWPS pull request, OWSLib issue, and Debian advisory. Affected product metadata is incomplete in the bundle, and OWSLib is described only as possibly affected. Do not claim exploit activity without new evidence.
Mitigation direction
- Upgrade PyWPS to 4.4.5 or later.
- Apply Debian LTS pywps security updates where applicable.
- Check vendor guidance before assuming OWSLib exposure or remediation.
- Limit access to affected XML-processing endpoints until patched.
- Review service account file permissions for unnecessary sensitive access.
Validation and detection
- Inventory PyWPS deployments and record exact versions.
- Confirm patched systems report PyWPS 4.4.5 or later.
- Verify Debian hosts include the referenced pywps security update.
- Identify public WPS/OWS endpoints that accept XML input.
- Review logs for suspicious XML entity activity without replaying payloads.
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-2021-39371 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://github.com/geopython/pywps/pull/616CVE reference · x_refsource_MISC
- https://github.com/geopython/OWSLib/issues/790CVE reference · x_refsource_MISC
- [debian-lts-announce] 20210904 [SECURITY] [DLA 2754-1] pywps 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.