Alertmanager: reject file-based http_headers in tenant configs - #7767
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Signed-off-by: Friedrich Gonzalez <1517449+friedrichg@users.noreply.github.com>
Signed-off-by: Friedrich Gonzalez <1517449+friedrichg@users.noreply.github.com>
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What this PR does: Rejects
http_config.http_headers.<NAME>.filesin per-tenant Alertmanager configs.prometheus/common'sheadersRoundTripperreads those paths at notification time and injects the contents into a request whose URL the tenant also controls, so a tenant with Alertmanager API access could disclose files readable by the Alertmanager process.http_headerswas the one setting missing from the*_filedenylist thatvalidateReceiverHTTPConfigalready applies.Only
Filesis rejected.ValuesandSecretsare inline literals and keep working.Affects v1.18.0 through v1.21.1. Only deployments with
-alertmanager.enable-api=trueare exposed.Tracked in GHSA-hq3h-j634-grmc.
Draft until the advisory is published. The CHANGELOG entry is intentionally non-specific and should be expanded with the CVE id at that point.