CVE-2026-111720: fish-island-backend through commit 7c61b78 SSRF via /api/web/parse

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-16 · updated 2026-10-19
Weakness: CWE-918

Description

fish-island-backend through commit 7c61b78 contains an unauthenticated server-side request forgery vulnerability that allows remote attackers to make the server fetch attacker-supplied URLs via the url parameter of GET /api/web/parse. Attackers can target internal hosts, loopback services or cloud metadata endpoints through redirect-following OkHttp requests and read back page titles, meta descriptions and favicons.

References

https://github.com/lhccong/fish-island-backend/blob/7c61b7861e99d3970beb34103c244b79e4de7d88/src/main/java/com/cong/fishisland/config/CorsConfig.java#L33
https://github.com/lhccong/fish-island-backend/blob/7c61b7861e99d3970beb34103c244b79e4de7d88/src/main/java/com/cong/fishisland/controller/chat/WebParserController.java#L13-L25
https://github.com/lhccong/fish-island-backend/blob/7c61b7861e99d3970beb34103c244b79e4de7d88/src/main/java/com/cong/fishisland/service/impl/chat/WebParserServiceImpl.java#L28-L45
https://hackmd.io/@hieuPenguinnn/fish-island-web-parse-unauth-ssrf
https://www.vulncheck.com/advisories/fish-island-backend-through-commit-7c61b78-ssrf-via-api-web-parse
https://hackmd.io/@hieuPenguinnn/fish-island-web-parse-unauth-ssrf

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