Vulnerability · Published May 26, 2026 · Assigned by GitHub_M

CVE-2026-44502Bugsink: SSRF bypass in `validate_webhook_url`

Medium 4.3

In plain English

A medium-severity server-side request forgery in bugsink from bugsink. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.3Medium

Exploit odds (30 days)0.3%top 78.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Bugsink is a self-hosted error tracking tool. Prior to 2.1.3, Bugsink’s webhook URL validation could be (partially) bypassed because of a mismatch in URL parsing. The original validation logic parsed webhook URLs with Python’s urllib.parse.urlparse, then sent the request with requests.post. For malformed inputs involving backslashes and @, those components can disagree about where the authority ends and which hostname is the real target. A URL may therefore appear to target an allowlisted public hostname during validation, while the HTTP client actually connects to a different host. This vulnerability is fixed in 2.1.3.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
PyPI	bugsink	2.1.3	GHSA-fp53-qcf8-2xx2
PyPI	bugsink	2.1.3	PYSEC-2026-2405

Affected products (as reported)

Vendor	Product	Versions
bugsink	bugsink	< 2.1.3

Weakness: CWE-918 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

References

https://github.com/bugsink/bugsink/security/advisories/GHSA-fp53-qcf8-2xx2 x_refsource_CONFIRM
https://github.com/bugsink/bugsink/commit/940d2df635e06803ef658666d734306942db5cc7 x_refsource_MISC
https://github.com/bugsink/bugsink/releases/tag/2.1.3 x_refsource_MISC