CVE-2011-4203
Moodle CRLF Injection Vulnerability in Calendar Component
CRLF injection vulnerability in calendar/set.php in the Calendar component in Moodle 1.9.x before 1.9.15, 2.0.x before 2.0.6, 2.1.x before 2.1.3, and 2.2 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via vectors involving the url variable.
Exploit likelihood
What each source reports
NVD Score used
CRLF injection vulnerability in calendar/set.php in the Calendar component in Moodle 1.9.x before 1.9.15, 2.0.x before 2.0.6, 2.1.x before 2.1.3, and 2.2 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via vectors involving the url variable.
- Record
CVE-2011-4203- CVSS 2.0
- 5.0 Medium
AV:N/AC:L/Au:N/C:N/I:P/A:N - Weakness
- CWE-94
- Updated
- 2026-11-02
CVE List No score
CRLF injection vulnerability in calendar/set.php in the Calendar component in Moodle 1.9.x before 1.9.15, 2.0.x before 2.0.6, 2.1.x before 2.1.3, and 2.2 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via vectors involving the url variable.
- Record
CVE-2011-4203- Updated
- 2026-11-02
EUVDEUVD-2022-2457 No score
CRLF injection vulnerability in calendar/set.php in the Calendar component in Moodle 1.9.x before 1.9.15, 2.0.x before 2.0.6, 2.1.x before 2.1.3, and 2.2 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via vectors involving the url variable.
- Record
EUVD-2022-2457- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-4w8m-96v9-2c86 No score
Moodle CRLF Injection Vulnerability in Calendar Component
CRLF injection vulnerability in calendar/set.php in the Calendar component in Moodle 1.9.x before 1.9.15, 2.0.x before 2.0.6, 2.1.x before 2.1.3, and 2.2 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via vectors involving the url variable.
- Record
GHSA-4w8m-96v9-2c86- Weakness
- CWE-93, CWE-113
- Updated
- 2026-11-02
OSVGHSA-4w8m-96v9-2c86 No score
Moodle CRLF Injection Vulnerability in Calendar Component
CRLF injection vulnerability in calendar/set.php in the Calendar component in Moodle 1.9.x before 1.9.15, 2.0.x before 2.0.6, 2.1.x before 2.1.3, and 2.2 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via vectors involving the url variable.
- Record
GHSA-4w8m-96v9-2c86- Weakness
- CWE-113, CWE-93
- Updated
- 2026-11-02
OSVUBUNTU-CVE-2011-4203 No score
CRLF injection vulnerability in calendar/set.php in the Calendar component in Moodle 1.9.x before 1.9.15, 2.0.x before 2.0.6, 2.1.x before 2.1.3, and 2.2 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via vectors involving the url variable.
- Record
UBUNTU-CVE-2011-4203- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
moodle/moodlePackagist |
before 1.9.15 | 1.9.15 |
moodle/moodlePackagist |
2.0 up to 2.0.6 | 2.0.6 |
moodle/moodlePackagist |
2.1 up to 2.1.3 | 2.1.3 |
moodleUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 2.7.9+dfsg-12.7.10+dfsg-12.7.11+dfsg-12.7.11+dfsg-22.7.12+dfsg-13.0.3+dfsg-0ubuntu13.0.3+dfsg-0ubuntu1+esm1 |
None known |
moodleUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 3.0.3+dfsg-0ubuntu13.0.3+dfsg-0ubuntu1+esm1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2011-4203 is a medium vulnerability (CVSS 5.0) in Moodle, published December 22, 2011. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.18%, the 67th percentile. Fixed in moodle/moodle 1.9.15.
References
tracker.moodle.org/browse/MDL-24808
penturalabs.wordpress.com/2011/12/13/advisory-crlf-injection-vulnerability-in-moodle
nvd.nist.gov/vuln/detail/CVE-2011-4203
github.com/moodle/moodle/commit/581e8dba387f090d89382115fd850d8b44351526