Description
January, the media proxy/embed service of stoatchat (stoatchat/stoatchat), before version 0.15.5 improperly resolves SVG <image href> values as local filesystem paths when a fetched resource is served as image/svg+xml. An unauthenticated remote attacker who causes the service to proxy an attacker-hosted SVG (e.g. via the /proxy endpoint) can determine whether local files exist through observable response-time differences, and can cause supported local image files to be disclosed after re-encoding. Because each referenced file is read in full with no effective limit on the number or total volume of reads, a single request can also generate an unbounded amount of local filesystem I/O and memory pressure (the published proof of concept drives about 4.34 GB of reads), leading to denial of service. The issue is fixed in 0.15.5.
References3
Metrics
- CVSS 3.1
-
8.2
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H - CVSS 4.0
-
8.8
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 43 · as of 9 November 2026
- CWE
- CWE-693
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