october: Improper Neutralization of Special Elements in Output Used by a Downstream Component
CVE-2022-21705 is a high-severity improper neutralization of special elements in output used by a downstream component vulnerability in october from OctoberCMS, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected october versions: < 1.0.474; >= 1.1.0, < 1.1.10; >= 2.0.0, < 2.1.27. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 8.65% chance of exploitation within 30 days, which is in the top 4.8% of all scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of october you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Octobercms | october | < 1.0.474; >= 1.1.0, < 1.1.10; >= 2.0.0, < 2.1.27 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- HighAdministrator-level access is required first.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.2 | High | CNA (github.com) |
| CVSS 3.1 | 7.2 | High | NVD |
| CVSS 2.0 | 8.5 | High | NVD |
Official description
Octobercms is a self-hosted CMS platform based on the Laravel PHP Framework. In affected versions user input was not properly sanitized before rendering. An authenticated user with the permissions to create, modify and delete website pages can exploit this vulnerability to bypass `cms.safe_mode` / `cms.enableSafeMode` in order to execute arbitrary code. This issue only affects admin panels that rely on safe mode and restricted permissions. To exploit this vulnerability, an attacker must first have access to the backend area. The issue has been patched in Build 474 (v1.0.474) and v1.1.10. Users unable to upgrade should apply https://github.com/octobercms/library/commit/c393c5ce9ca2c5acc3ed6c9bb0dab5ffd61965fe to your installation manually.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Special Elements in Output Used by a Downstream Component
The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.
How developers prevent this class of flaw
- Programming languages and supporting technologies might be chosen which are not subject to these issues.
- Utilize an appropriate mix of allowlist and denylist parsing to filter control-plane syntax from all input.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- github.com/octobercms/october/security/advisories/GHSA-79jw-2f46-wv22Issue Tracking, Third Party Advisory
Patches and release notes
- github.com/octobercms/library/commit/c393c5ce9ca2c5acc3ed6c9bb0dab5ffd61965feThird Party Advisory
Other vulnerabilities in october
- 9.1 Critical severity
- 7.2 High severity
- 8.1 High severity
- 9.1 Critical severity
October CMS Improper Authentication Exploited
Recent Improper Neutralization of Special Elements in Output Used by a Downstream Component vulnerabilities
- 7.5 High severity
- 8.8 High severity
- 9.8 Critical severity
- 8.8 High severity
- 7.5 High severity
- 9.8 Critical severity
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