Authentication mechanism absence or evasion In github.com/matrix-org/gomatrixserverlib
Description
gomatrixserverlib and Dendrite vulnerable to incorrect parsing of the event default power level in event auth
Impact
The power level parsing within gomatrixserverlib was failing to parse the "events_default" key of the m.room.power_levels event, defaulting the event default power level to zero in all cases.
In rooms where the "events_default" power level had been changed, this could result in events either being incorrectly authorised or rejected by Dendrite servers.
Patches
gomatrixserverlib contains a fix as of commit 723fd49 and Dendrite 0.9.3 has been updated accordingly.
Workarounds
Matrix rooms where the "events_default" power level has not been changed from the default of zero are not vulnerable.
For more information
If you have any questions or comments about this advisory, e-mail us at [email protected].
Mitigation
Update Impact
Minimal update. May introduce new vulnerabilities or breaking changes.
Ecosystem | Package | Affected version | Patched versions |
|---|---|---|---|
 go | 0.0.0-20220815091947-723fd495dde8 | ||
go | 0.9.3 |
Aliases
References