gosaml2 vulnerable to Denial Of Service Via Deflate Decompression Bomb
Date: 2023-03
Affected: go/github.com/russellhaering/gosaml2
Attack vector: dos
Category: vulnerability-disclosure
Severity: Medium
CVE: CVE-2023-26483
CWE: CWE-409
CVSS: 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)

### Impact SAML Service Providers using this library for SAML authentication support are likely susceptible to Denial of Service attacks. A bug in this library enables attackers to craft a `deflate`-compressed request which will consume significantly more memory during processing than the size of the original request. This may eventually lead to memory exhaustion and the process being killed. ### Mitigation The maximum compression ratio achievable with `deflate` is 1032:1, so by limiting the size of bodies passed to gosaml2, limiting the rate and concurrency of calls, and ensuring that lots of memory is available to the process it _may_ be possible to help Go's garbage collector "keep up". Implementors are encouraged not to rely on this. ### Patches This issue is addressed in v0.9.0


Mitigations:

Architectural layers (MAESTRO):