CVE-2021-32792: XSS vulnerability when using OIDCPreservePost On in mod_auth_openidc
Noroxi assessment
Priority: Monitor (action score 24/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 1.5% (FIRST EPSS); higher than 74.6% of all records.
- Anyone who can reach it over the internet can trigger it. No account or password is required. A user must open a link or visit a page. No special conditions are required; it is repeatable.
- Fixed version: cjose (AlmaLinux:8) 0.6.1-2.module_el8.6.0+2868+44838709; cjose-devel (AlmaLinux:8) 0.6.1-2.module_el8.6.0+2868+44838709; mod_auth_openidc (AlmaLinux:8) 2.3.7-11.module_el8.6.0+2868+44838709.
- Severity is disputed: the assigning authority (CNA) scores it 3.1, NVD 6.1.
Low priority for now. Upgrade to cjose (AlmaLinux:8) 0.6.1-2.module_el8.6.0+2868+44838709; cjose-devel (AlmaLinux:8) 0.6.1-2.module_el8.6.0+2868+44838709; mod_auth_openidc (AlmaLinux:8) 2.3.7-11.module_el8.6.0+2868+44838709 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
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`.
- Published
- Jul 26, 2021
- Updated
- Jun 16, 2026
- EPSS
- 1.5% · 74th percentile
- CWE
- CWE-79
Report tools
Action score
24
Monitor
Low priority for now.
- CVSS
- 24 / 40 · 6.1 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 1.5%
CNA vs NVD score
- NVD
- 6.1
- CNA · GitHub_M
- 3.1
- 3.0 point gap
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:N/A:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| openidc | mod auth openidc | cpe:2.3:a:openidc:mod_auth_openidc |
| apache | http server | cpe:2.3:a:apache:http_server |
| fedoraproject | fedora | cpe:2.3:o:fedoraproject:fedora |
Limit the impact of XSS
This is a cross-site scripting (XSS) vulnerability. A well-configured Content-Security-Policy doesn't fix it, but greatly reduces its impact. Check your site's CSP and other security headers for free.
Check security headersAffected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- fedoraproject fedora33
- fedoraproject fedora34
- openidc mod auth openidcbefore 2.4.9
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
zmartzone mod_auth_openidc
- < 2.4.9affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:8 | cjose | before 0.6.1-2.module_el8.6.0+2868+44838709 | 0.6.1-2.module_el8.6.0+2868+44838709 |
| AlmaLinux:8 | cjose-devel | before 0.6.1-2.module_el8.6.0+2868+44838709 | 0.6.1-2.module_el8.6.0+2868+44838709 |
| AlmaLinux:8 | mod_auth_openidc | before 2.3.7-11.module_el8.6.0+2868+44838709 | 2.3.7-11.module_el8.6.0+2868+44838709 |
| Debian:10 | libapache2-mod-auth-openidc | before 2.3.10.2-1+deb10u2 | 2.3.10.2-1+deb10u2 |
| Debian:12 | libapache2-mod-auth-openidc | before 2.4.9-1 | 2.4.9-1 |
| openSUSE:Leap 15.2 | apache2-mod_auth_openidc | before 2.3.8-lp152.5.6.1 | 2.3.8-lp152.5.6.1 |
| openSUSE:Leap 15.3 | apache2-mod_auth_openidc | before 2.3.8-3.15.1 | 2.3.8-3.15.1 |
| openSUSE:Leap 15.6 | apache2-mod_auth_openidc | before 2.4.17.1-150600.16.14.1 | 2.4.17.1-150600.16.14.1 |
| Red Hat:enterprise_linux:8::appstream | cjose | before 0:0.6.1-2.module+el8+2454+f890a43a | 0:0.6.1-2.module+el8+2454+f890a43a |
| Red Hat:enterprise_linux:8::appstream | cjose-debuginfo | before 0:0.6.1-2.module+el8+2454+f890a43a | 0:0.6.1-2.module+el8+2454+f890a43a |
| Red Hat:enterprise_linux:8::appstream | cjose-debugsource | before 0:0.6.1-2.module+el8+2454+f890a43a | 0:0.6.1-2.module+el8+2454+f890a43a |
| Red Hat:enterprise_linux:8::appstream | cjose-devel | before 0:0.6.1-2.module+el8+2454+f890a43a | 0:0.6.1-2.module+el8+2454+f890a43a |
| Red Hat:enterprise_linux:8::appstream | mod_auth_openidc | before 0:2.3.7-11.module+el8.6.0+14082+b6f23e95 | 0:2.3.7-11.module+el8.6.0+14082+b6f23e95 |
| Red Hat:enterprise_linux:8::appstream | mod_auth_openidc-debuginfo | before 0:2.3.7-11.module+el8.6.0+14082+b6f23e95 | 0:2.3.7-11.module+el8.6.0+14082+b6f23e95 |
| Red Hat:enterprise_linux:8::appstream | mod_auth_openidc-debugsource | before 0:2.3.7-11.module+el8.6.0+14082+b6f23e95 | 0:2.3.7-11.module+el8.6.0+14082+b6f23e95 |
| Rocky Linux:8 | cjose | before 0:0.6.1-2.module+el8.3.0+129+2feafa46 | 0:0.6.1-2.module+el8.3.0+129+2feafa46 |
| Rocky Linux:8 | mod_auth_openidc | before 0:2.3.7-11.module+el8.6.0+840+73eca44e | 0:2.3.7-11.module+el8.6.0+840+73eca44e |
| SUSE:Linux Enterprise Module for Server Applications 15 SP2 | apache2-mod_auth_openidc | before 2.3.8-3.15.1 | 2.3.8-3.15.1 |
| SUSE:Linux Enterprise Module for Server Applications 15 SP6 | apache2-mod_auth_openidc | before 2.4.17.1-150600.16.14.1 | 2.4.17.1-150600.16.14.1 |
| SUSE:Linux Enterprise Server 12 SP5 | apache2-mod_auth_openidc | before 2.4.0-3.23.1 | 2.4.0-3.23.1 |
Same product
openidc: all recordsOther highest-scoring records for the same primary product.
- CVE-2017-6413The "OpenID Connect Relying Party and OAuth 2.0 Resource Server" (aka mod_auth_openidc) module before 2.1.6 for the Apache HTTP Server does 35Monitor
- CVE-2017-6062The "OpenID Connect Relying Party and OAuth 2.0 Resource Server" (aka mod_auth_openidc) module before 2.1.5 for the Apache HTTP Server does 35Monitor
- CVE-2017-6059Mod_auth_openidc.c in the Ping Identity OpenID Connect authentication module for Apache (aka mod_auth_openidc) before 2.14 allows remote att32Monitor
Published before and after this one in the same product
- ← EarlierCVE-2021-32786Jul 22, 2021 · Open Redirect in oidc_validate_redirect_url()25Monitor
- ← EarlierCVE-2021-32791Jul 26, 2021 · Hardcoded static IV and AAD with a reused key in AES GCM encryption in mod_auth_openidc23Monitor
- Later →CVE-2021-39191Sep 3, 2021 · URL Redirection to Untrusted Site ('Open Redirect') in mod_auth_openidc25Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| almalinux:cjose | 0.6.1-2.module_el8.6.0+2868+44838709 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:cjose-devel | 0.6.1-2.module_el8.6.0+2868+44838709 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:mod_auth_openidc | 2.3.7-11.module_el8.6.0+2868+44838709 · AlmaLinux:8 | Package registry (OSV) |
| debian:libapache2-mod-auth-openidc | 2.4.9-1 · Debian:12 | Package registry (OSV) |
| opensuse:apache2-mod_auth_openidc | 2.4.17.1-150600.16.14.1 · openSUSE:Leap 15.6 | Package registry (OSV) |
| red hat:cjose | 0:0.6.1-2.module+el8+2454+f890a43a · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:cjose-debuginfo | 0:0.6.1-2.module+el8+2454+f890a43a · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:cjose-debugsource | 0:0.6.1-2.module+el8+2454+f890a43a · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:cjose-devel | 0:0.6.1-2.module+el8+2454+f890a43a · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:mod_auth_openidc | 0:2.3.7-11.module+el8.6.0+14082+b6f23e95 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:mod_auth_openidc-debuginfo | 0:2.3.7-11.module+el8.6.0+14082+b6f23e95 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| red hat:mod_auth_openidc-debugsource | 0:2.3.7-11.module+el8.6.0+14082+b6f23e95 · Red Hat:enterprise_linux:8::appstream | Package registry (OSV) |
| rocky linux:cjose | 0:0.6.1-2.module+el8.3.0+129+2feafa46 · Rocky Linux:8 | Package registry (OSV) |
| rocky linux:mod_auth_openidc | 0:2.3.7-11.module+el8.6.0+840+73eca44e · Rocky Linux:8 | Package registry (OSV) |
| suse:apache2-mod_auth_openidc | 2.3.8-3.15.1 · SUSE:Linux Enterprise Module for Server Applications 15 SP2 | Package registry (OSV) |
| suse:apache2-mod_auth_openidc | 2.4.17.1-150600.16.14.1 · SUSE:Linux Enterprise Module for Server Applications 15 SP6 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
No history yet (it accumulates with the daily EPSS job).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- A user must open a link or visit a page.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- low · data can be read
- Integrity
- low · data or configuration can be modified
- Availability
- none
Impact can extend beyond the vulnerable component (scope changes).
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Changed
- Confidentiality impact
- Low
- Integrity impact
- Low
- Availability impact
- None
Weakness class (CWE)
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
nvd-primary
Root cause
User content is inserted into the page as HTML. The browser interprets the content as code rather than data.
The bug in code
The whole CWE-79 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
commentEl.innerHTML = comment.body;Fixed
commentEl.textContent = comment.body;Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (7 more)Show less
- github.com/zmartzone/mod_auth_openidc/commit/55ea0a085290cd2c8cdfdd960a230cbc38ba8b56
- github.com/zmartzone/mod_auth_openidc/releases/tag/v2.4.9
- github.com/zmartzone/mod_auth_openidc/security/advisories/GHSA-458c-7pwg-3j7j
- lists.debian.org/debian-lts-announce/2023/04/msg00034.html
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FZVF6BSJLRQZ7PFFR4X5JSU6KUJYNOCU/
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/QXAWKPT5LXZSUTFSJ6IWSZC7RMYYQXQD/
- www.oracle.com/security-alerts/cpuapr2022.html
Vendor advisories and official records. Exploit/PoC links are deliberately left out.