CVE-2026-6339
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2026
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
Missing request origin validation on burn-on-read reveal endpoint
Mattermost versions 11.5.x <= 11.5.1, 11.4.x <= 11.4.3 fail to validate the X-Requested-With header on the burn-on-read reveal endpoint which allows an authenticated channel member to force the reveal of a burn-on-read message without recipient consent via a crafted Markdown image tag.. Mattermost Advisory ID: MMSA-2026-00636
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
Mattermost
- Vendor
- Mattermost
- Product
- Mattermost
- Platforms
- Unknown
- Default status
unaffected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 11.5.0 | affected | semver | Unavailable | 11.5.1 | None listed |
| 11.4.0 | affected | semver | Unavailable | 11.4.3 | None listed |
| 11.6.0 | unaffected | Unavailable | Unavailable | Unavailable | None listed |
| 11.5.2 | unaffected | Unavailable | Unavailable | Unavailable | None listed |
| 11.4.4 | unaffected | Unavailable | Unavailable | Unavailable | None listed |