CVE-2023-23611
xblock-lti-consumer contain Missing Authorization in Grade Pass Back Implementation
LTI Consumer XBlock implements the consumer side of the LTI specification enabling integration of third-party LTI provider tools. Versions 7.0.0 and above, prior to 7.2.2, are vulnerable to Missing Authorization. Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows or can guess the block location for that XBlock. An LTI tool submits scores to the edX platform for line items. The code that uploads that score to the LMS grade tables determines which XBlock to upload the grades for by reading the resource_link_id field of the associated line item. The LTI tool may submit any value for the resource_link_id field, allowing a malicious LTI tool to submit scores for any LTI XBlock on the platform. The impact is a loss of integrity for LTI XBlock grades. This issue is patched in 7.2.2. No workarounds exist.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
5.4
xblock-lti-consumer contain Missing Authorization in Grade Pass Back Implementation
LTI Consumer XBlock implements the consumer side of the LTI specification enabling integration of third-party LTI provider tools. Versions 7.0.0 and above, prior to 7.2.2, are vulnerable to Missing Authorization. Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows or can guess the block location for that XBlock. An LTI tool submits scores to the edX platform for line items. The code that uploads that score to the LMS grade tables determines which XBlock to upload the grades for by reading the resource_link_id field of the associated line item. The LTI tool may submit any value for the resource_link_id field, allowing a malicious LTI tool to submit scores for any LTI XBlock on the platform. The impact is a loss of integrity for LTI XBlock grades. This issue is patched in 7.2.2. No workarounds exist.
- Record
CVE-2023-23611- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
EUVDEUVD-2023-0127
5.4
LTI Consumer XBlock implements the consumer side of the LTI specification enabling integration of third-party LTI provider tools. Versions 7.0.0 and above, prior to 7.2.2, are vulnerable to Missing Authorization. Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows or can guess the block location for that XBlock. An LTI tool submits scores to the edX platform for line items. The code that uploads that score to the LMS grade tables determines which XBlock to upload the grades for by reading the resource_link_id field of the associated line item. The LTI tool may submit any value for the resource_link_id field, allowing a malicious LTI tool to submit scores for any LTI XBlock on the platform. The impact is a loss of integrity for LTI XBlock grades. This issue is patched in 7.2.2. No workarounds exist.
- Record
EUVD-2023-0127- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-7j9p-67mm-5g87
2.1
LTI 1.3 Grade Pass Back Implementation has Missing Authorization Vulnerability
Problem
TL;DR: Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows or can guess the block location for that XBlock.
In LTI 1.3, LTI tools can "pass back" scores that learners earn while using LTI tools to the edX platform. The edX platform then stores those LTI scores in a separate table. If the right conditions are met, these scores are then persisted to the LMS grades tables.
LTI tools can create what are called "line items" on the edX platform. A line item can be thought of as a column in a grade book; it stores results for a specific activity (i.e. XBlock) for a specific set of users (i.e. users in the course using the XBlock). A line item has an optional resource_link_id field, which is basically the XBlock location. An LTI tool can supply any value for this field.
An LTI tool submits scores to the edX platform for line items. The code that uploads that score to the LMS grade tables determines which XBlock to upload the grades for by reading the resource_link_id field of the associated line item. Because the LTI tool could have submitted any value for the resource_link_id field, this introduces the potential for a nefarious LTI tool to submit scores for any LTI XBlock on the platform.
Impact
Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows the resource_link_id (i.e. block location) for that XBlock.
The impact is a loss of integrity for LTI XBlock grades.
Patches
No available patch
Workarounds
No
- Record
GHSA-7j9p-67mm-5g87- CVSS 4.0
- 2.1 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
NVD
5.4
LTI Consumer XBlock implements the consumer side of the LTI specification enabling integration of third-party LTI provider tools. Versions 7.0.0 and above, prior to 7.2.2, are vulnerable to Missing Authorization. Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows or can guess the block location for that XBlock. An LTI tool submits scores to the edX platform for line items. The code that uploads that score to the LMS grade tables determines which XBlock to upload the grades for by reading the resource_link_id field of the associated line item. The LTI tool may submit any value for the resource_link_id field, allowing a malicious LTI tool to submit scores for any LTI XBlock on the platform. The impact is a loss of integrity for LTI XBlock grades. This issue is patched in 7.2.2. No workarounds exist.
- Record
CVE-2023-23611- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
OSV
5.4
xblock-lti-consumer contain Missing Authorization in Grade Pass Back Implementation
LTI Consumer XBlock implements the consumer side of the LTI specification enabling integration of third-party LTI provider tools. Versions 7.0.0 and above, prior to 7.2.2, are vulnerable to Missing Authorization. Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows or can guess the block location for that XBlock. An LTI tool submits scores to the edX platform for line items. The code that uploads that score to the LMS grade tables determines which XBlock to upload the grades for by reading the resource_link_id field of the associated line item. The LTI tool may submit any value for the resource_link_id field, allowing a malicious LTI tool to submit scores for any LTI XBlock on the platform. The impact is a loss of integrity for LTI XBlock grades. This issue is patched in 7.2.2. No workarounds exist.
- Record
CVE-2023-23611- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
OSVGHSA-7j9p-67mm-5g87
2.1
LTI 1.3 Grade Pass Back Implementation has Missing Authorization Vulnerability
Problem
TL;DR: Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows or can guess the block location for that XBlock.
In LTI 1.3, LTI tools can "pass back" scores that learners earn while using LTI tools to the edX platform. The edX platform then stores those LTI scores in a separate table. If the right conditions are met, these scores are then persisted to the LMS grades tables.
LTI tools can create what are called "line items" on the edX platform. A line item can be thought of as a column in a grade book; it stores results for a specific activity (i.e. XBlock) for a specific set of users (i.e. users in the course using the XBlock). A line item has an optional resource_link_id field, which is basically the XBlock location. An LTI tool can supply any value for this field.
An LTI tool submits scores to the edX platform for line items. The code that uploads that score to the LMS grade tables determines which XBlock to upload the grades for by reading the resource_link_id field of the associated line item. Because the LTI tool could have submitted any value for the resource_link_id field, this introduces the potential for a nefarious LTI tool to submit scores for any LTI XBlock on the platform.
Impact
Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows the resource_link_id (i.e. block location) for that XBlock.
The impact is a loss of integrity for LTI XBlock grades.
Patches
No available patch
Workarounds
No
- Record
GHSA-7j9p-67mm-5g87- CVSS 4.0
- 2.1 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 3.7 Low
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N - Weakness
- CWE-862
- Updated
- 2026-11-02
OSVPYSEC-2023-21 No score
LTI Consumer XBlock implements the consumer side of the LTI specification enabling integration of third-party LTI provider tools. Versions 7.0.0 and above, prior to 7.2.2, are vulnerable to Missing Authorization. Any LTI tool that is integrated with on the Open edX platform can post a grade back for any LTI XBlock so long as it knows or can guess the block location for that XBlock. An LTI tool submits scores to the edX platform for line items. The code that uploads that score to the LMS grade tables determines which XBlock to upload the grades for by reading the resource_link_id field of the associated line item. The LTI tool may submit any value for the resource_link_id field, allowing a malicious LTI tool to submit scores for any LTI XBlock on the platform. The impact is a loss of integrity for LTI XBlock grades. This issue is patched in 7.2.2. No workarounds exist.
- Record
PYSEC-2023-21- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
lti-consumer-xblockPyPI |
7.0.0 up to 7.2.2 | 7.2.2 |
lti-consumer-xblockPyPI |
7.0.0 up to 7.2.2, plus listed versions 7.0.17.0.27.0.37.1.07.2.07.2.1 |
7.2.2 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-23611 is a medium vulnerability (CVSS 5.4) in Openedx Xblock-lti-consumer, published January 25, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.39%, the 33rd percentile. Fixed in lti-consumer-xblock 7.2.2.
References
github.com/openedx/xblock-lti-consumer/security/advisories/GHSA-7j9p-67mm-5g87
nvd.nist.gov/vuln/detail/CVE-2023-23611
github.com/openedx/xblock-lti-consumer/commit/252f94bd182cd0962af9251015930cb55ec515d7
github.com/pypa/advisory-database/tree/main/vulns/lti-consumer-xblock/PYSEC-2023-21.yaml
github.com/advisories/GHSA-7j9p-67mm-5g87
github.com/CVEProject/cvelistV5/tree/main/cves/2023/23xxx/CVE-2023-23611.json
github.com/openedx/xblock-lti-consumer