How severe is CVE-2026-33737?

CVE-2026-33737 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2026-33737 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-33737?

CVE-2026-33737 primarily affects Chamilo Chamilo Lms. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-33737?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-33737 have an EU (EUVD) identifier?

Yes. CVE-2026-33737 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21569.

When was CVE-2026-33737 published?

CVE-2026-33737 was published on 2026-04-10 and last updated on 2026-06-17.

CVE-2026-33737

CVE-2026-33737 is a medium-severity vulnerability in Chamilo Chamilo Lms with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-611.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-21569
Weakness: CWE-611
Affected product: Chamilo Chamilo Lms
Published: 2026-04-10
Last modified: 2026-06-17

Description

Chamilo LMS is a learning management system. Prior to 1.11.38 and 2.0.0-RC.3, multiple files use simplexml_load_string() without XXE protection. With LIBXML_NOENT flag, arbitrary server files can be read. This vulnerability is fixed in 1.11.38 and 2.0.0-RC.3.

Frequently asked questions

What is CVE-2026-33737?: Chamilo LMS is a learning management system. Prior to 1.11.38 and 2.0.0-RC.3, multiple files use simplexml_load_string() without XXE protection. With LIBXML_NOENT flag, arbitrary server files can be read. This vulnerability is fixed in 1.11.38 and 2.0.0-RC.3.
How severe is CVE-2026-33737?: CVE-2026-33737 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2026-33737 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-33737?: CVE-2026-33737 primarily affects Chamilo Chamilo Lms. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-33737?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-33737 have an EU (EUVD) identifier?: Yes. CVE-2026-33737 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-21569.
When was CVE-2026-33737 published?: CVE-2026-33737 was published on 2026-04-10 and last updated on 2026-06-17.

References

Affected products (11)

cpe:2.3:a:chamilo:chamilo_lms:*:*:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:alpha1:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:alpha2:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:alpha3:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:alpha4:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:alpha5:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:beta1:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:beta2:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:beta3:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:rc1:*:*:*:*:*:*
cpe:2.3:a:chamilo:chamilo_lms:2.0.0:rc2:*:*:*:*:*:*

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