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CVE Record

CVE-2021-32792: XSS vulnerability when using OIDCPreservePost On in mod_auth_openidc

mod_auth_openidc is an authentication/authorization module for the Apache 2.x HTTP server that functions as an OpenID Connect Relying Party, authenticating users against an OpenID Connect Provider. In mod_auth_openidc before version 2.4.9, there is an XSS vulnerability in when using `OIDCPreservePost On`.

LowCVSS 3.1Not KEV-listedUpdated
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Glexia's TakeAutomated analysislow

Security readout for executives and security teams

Plain-English summary

CVE-2021-32792 is a low-severity cross-site scripting issue in Apache deployments using mod_auth_openidc before 2.4.9 with OIDCPreservePost On. A victim would need to interact with a crafted flow, and the documented impact is limited confidentiality exposure, not system takeover.

Executive priority

Schedule remediation in the normal web application security patch cycle, faster for internet-facing authentication services. This is not evidenced as actively exploited, but authentication-layer XSS can still create business exposure if left unresolved.

Technical view

The vulnerable component is zmartzone mod_auth_openidc, an Apache 2.x OpenID Connect relying-party module. Versions before 2.4.9 can expose XSS behavior only when OIDCPreservePost is enabled. CVSS 3.1 is 3.1 with network attack vector, high complexity, no privileges, required user interaction, and low confidentiality impact.

Likely exposure

Exposure is likely limited to Apache servers running mod_auth_openidc below 2.4.9 and configured with OIDCPreservePost On. Internet-facing authentication front ends deserve priority review, but the source bundle does not indicate broad default exposure.

Exploitation context

The source bundle does not show CISA KEV listing or active exploitation evidence. The CVSS vector indicates exploitation is remote but high-complexity and requires user interaction. Treat this as a targeted web-authentication risk rather than an emergency infrastructure compromise.

Researcher notes

Focus validation on the OIDCPreservePost On condition and version boundary before 2.4.9. The bundle cites upstream advisory, release, and commits, but does not provide operational exploit details or evidence of active exploitation.

Mitigation direction

  • Upgrade mod_auth_openidc to 2.4.9 or a supported vendor-fixed package.
  • Apply relevant Fedora, Debian LTS, or Oracle security updates where those distributions are used.
  • Identify deployments with OIDCPreservePost On and prioritize them for remediation.
  • If patching is delayed, check vendor guidance; sources do not name an alternate mitigation.

Validation and detection

  • Inventory Apache hosts that load the mod_auth_openidc module.
  • Confirm installed mod_auth_openidc versions are 2.4.9 or vendor-fixed builds.
  • Review Apache configuration for OIDCPreservePost On.
  • Confirm package provenance against Fedora, Debian LTS, Oracle, or upstream release advisories.
  • Review web security telemetry for suspicious script-injection attempts around authentication flows.
Prepared
Confidence
high
Sources
10

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

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 · medium confidence lookup

CWE-79: User-session and phishing behavior lookup

Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. 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 lookup
cve · low confidence lookup

CVE-2021-32792 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
Low
CVSS
3.1 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

Official CVE source material

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.

1CVSS vectors
0Timeline events
0ADP providers
9Source links

CVSS vector scores

1 official score

We 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.

ScoreVersionSeverityVectorExploitImpactSource
3.1CVSS 3.1LowCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N1.61.4Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

3.1Low
CVSS 3.1 vector shape for CVE-2021-32792Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
zmartzonemod_auth_openidc< 2.4.9Listed
Weakness

CWE details

CWE-79

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.