CVE-2026-100676

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.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/stoatchat/stoatchat/security/advisories/GHSA-qv38-hwhv-jm49
https://www.vulncheck.com/advisories/stoatchat-before-0.15.5-local-filesystem-read-via-svg
https://github.com/stoatchat/stoatchat/security/advisories/GHSA-qv38-hwhv-jm49

Configurations

No configuration.

History

28 Sep 2026, 17:17

Type	Values Removed	Values Added
References	~~() https://github.com/stoatchat/stoatchat/security/advisories/GHSA-qv38-hwhv-jm49 -~~	() https://github.com/stoatchat/stoatchat/security/advisories/GHSA-qv38-hwhv-jm49 -

26 Sep 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-26 14:16

Updated : 2026-09-28 17:17

NVD link : CVE-2026-100676

Mitre link : CVE-2026-100676

CVE.ORG link : CVE-2026-100676

JSON object : View

Products Affected

No product.

CWE

CWE-693

Protection Mechanism Failure

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