CVE-2026-1691
Remote Deserialization Vulnerability in bolo-solo SnakeYAML Component
Publication date: 2026-01-30
Last updated on: 2026-04-29
Assigner: VulDB
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| adlered | bolo-solo | to 2.6.4 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-502 | The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid. |
| CWE-20 | The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
CVE-2026-1691 is a deserialization vulnerability in bolo-solo up to version 2.6.4, specifically in the importMarkdownsSync function of BackupService.java. The vulnerability arises because the application uses the SnakeYAML library to deserialize YAML content from user-uploaded markdown files without secure loading or validation. This allows an attacker to craft malicious YAML payloads that, when processed, lead to arbitrary code execution on the server remotely. The exploit involves uploading a markdown file containing a malicious YAML payload that triggers unsafe deserialization, enabling execution of attacker-controlled code. [1, 2, 3]
How can this vulnerability impact me? :
This vulnerability can allow a remote attacker to execute arbitrary code on the affected server without authentication. By exploiting the insecure YAML deserialization, an attacker can gain full control over the target system, potentially compromising confidentiality, integrity, and availability of the system and its data. This could lead to unauthorized access, data breaches, service disruption, or further attacks launched from the compromised server. [1, 2, 3]
How can this vulnerability be detected on my network or system? Can you suggest some commands?
Detection can involve monitoring for uploads of malicious markdown files containing crafted YAML payloads to the /import/markdown interface of bolo-solo. Since the vulnerability is exploited by uploading specially crafted markdown files that trigger unsafe deserialization, inspecting logs for such uploads or scanning for unusual activity related to the importMarkdownsSync function may help. However, no specific detection commands are provided in the resources. [1, 2, 3]
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation steps include preventing the upload of untrusted markdown files to the /import/markdown interface, disabling or restricting the importMarkdownsSync functionality, and avoiding use of the vulnerable bolo-solo versions (up to 2.6.4). Since no known countermeasures or mitigations currently exist, replacing or patching the affected component (SnakeYAML usage in BackupService.java) to use secure YAML loading practices is recommended. Monitoring for updates or patches from the vendor is also advised. [3, 1, 2]