CVE-2026-104817 (GCVE-0-2026-104817)
Vulnerability from cvelistv5 – Published: 2026-10-13 18:39 – Updated: 2026-10-13 19:04
VLAI
EPSS
VEX
Title
Misskey: Lack of rate limiting and size restrictions in RSS fetching API
Summary
Misskey is an open source, federated social media platform. From 12.112.1 until 2026.7.0, the unauthenticated fetch-rss API lacks rate limiting and response-size restrictions and performs synchronous XML parsing. An attacker can trigger unbounded outbound HTTP requests and synchronous parsing, exhausting instance resources, amplifying requests toward third-party servers, or probing network-reachable services even when federation is disabled. This issue is fixed in version 2026.7.0.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-13 19:03 UTC
CWE
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/misskey-dev/misskey/security/a… | x_refsource_CONFIRM |
| https://github.com/misskey-dev/misskey/commit/a12… | x_refsource_MISC |
| https://github.com/misskey-dev/misskey/releases/t… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| misskey-dev | misskey |
Affected:
>= 12.0.0, <= 13.14.2
Affected: >= 2023.9.0-beta.1, < 2026.7.0 |
guessed |
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| Author | Source | Type | Date | Other |
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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