GHSA-5X67-J5XG-C5GJ
Vulnerability from github – Published: 2026-06-05 21:45 – Updated: 2026-06-12 19:24Summary
In affected versions, Bugsink stores every tag supplied with an incoming event. An event with an unusually large number of custom (i.e. supplied by an attacker) tags can therefore make ingestion spend more time than intended writing tag rows.
Bugsink uses a single-writer database architecture. That keeps the implementation simple, but it also means one expensive write transaction can delay other event digestion while it is running. In this case, it makes ingestion of other events wait until the transaction that writes the tags finishes, which effectively causes a temporary denial of service for other events.
Impact
Submitting such an event requires a valid project DSN. DSNs are sometimes visible in client-side applications, so they should not be treated as a strong security boundary, but the issue is still limited to ingestion for a Bugsink instance that accepts the event.
The impact is availability-only. The issue does not expose stored data, modify existing events, or allow code execution.
Mitigation
Update to version 2.2.2, which caps the number of tags stored for a single event. The default cap is 100 tags and can
be changed with MAX_EVENT_TAGS.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 2.2.1"
},
"package": {
"ecosystem": "PyPI",
"name": "bugsink"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.2.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-53954"
],
"database_specific": {
"cwe_ids": [
"CWE-400"
],
"github_reviewed": true,
"github_reviewed_at": "2026-06-05T21:45:40Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "### Summary\n\nIn affected versions, Bugsink stores every tag supplied with an incoming event. An event with an unusually large number\nof custom (i.e. supplied by an attacker) tags can therefore make ingestion spend more time than intended writing tag rows.\n\nBugsink uses a single-writer database architecture. That keeps the implementation simple, but it also means one\nexpensive write transaction can delay other event digestion while it is running. In this case, it makes ingestion of\nother events wait until the transaction that writes the tags finishes, which effectively causes a temporary denial of\nservice for other events.\n\n### Impact\n\nSubmitting such an event requires a valid project DSN. DSNs are sometimes visible in client-side applications, so they\nshould not be treated as a strong security boundary, but the issue is still limited to ingestion for a Bugsink instance\nthat accepts the event.\n\nThe impact is availability-only. The issue does not expose stored data, modify existing events, or allow code execution.\n\n### Mitigation\n\nUpdate to version 2.2.2, which caps the number of tags stored for a single event. The default cap is 100 tags and can\nbe changed with `MAX_EVENT_TAGS`.",
"id": "GHSA-5x67-j5xg-c5gj",
"modified": "2026-06-12T19:24:20Z",
"published": "2026-06-05T21:45:40Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/bugsink/bugsink/security/advisories/GHSA-5x67-j5xg-c5gj"
},
{
"type": "PACKAGE",
"url": "https://github.com/bugsink/bugsink"
},
{
"type": "WEB",
"url": "https://github.com/bugsink/bugsink/releases/tag/2.2.2"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
"type": "CVSS_V3"
}
],
"summary": "Bugsink: DOS using large numbers of event tags"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.