We ship an Endpoint Security system extension inside a host app. On one managed Mac (macOS 26.6.2, build 25G83, arm64) the extension can't be activated, while the same package works on other Macs with the same macOS build.
WHAT WE SHIP AND HOW IT'S NOTARIZED
Host app: ElasticEndpoint.app (co.elastic.endpoint), Developer ID signed, notarized, with the ticket stapled (codesign -dvv shows "Notarization Ticket=stapled").
System extension: ElasticEndpoint.app/Contents/Library/SystemExtensions/co.elastic.systemextension.systemextension (co.elastic.systemextension), same Team ID, Developer ID signed. It was part of the same notarization submission as the host app but has no ticket stapled to itself (stapler validate says "does not have a ticket stapled to it").
Delivery: a root-owned service extracts the app into /Applications with tar (so no quarantine attribute) and then runs "ElasticEndpoint --install" as root to request activation.
Versions: first reported on 9.0.8, and the same on 9.5.1. 9.1.0 and 9.5.4 have the same layout.
Public packages: https://artifacts.elastic.co/downloads/beats/elastic-agent/elastic-agent-9.0.8-darwin-aarch64.tar.gz , with the app in data/elastic-agent-*/components/endpoint-security-resources.zip -> 64_Bit_Elastic_App_macOS.tgz. The 9.5.1 package is at the same URL pattern.
SYMPTOMS ON THE AFFECTED MAC
syspolicyd: [com.apple.syspolicy:default] Unable to parse ticket.
syspolicyd: [com.apple.syspolicy:default] error registering ticket: -1
sysextd: Error checking with notarization daemon: 3
sysextd: bundle code signature is not valid - does not satisfy requirement: -67050 code failed to satisfy specified code requirement(s)
sysextd: co.elastic.systemextension: extension failed to validate! uninstalling...
"spctl -a -vv -t execute" prints "accepted / source=Developer ID", not "Notarized Developer ID", for our app and for an unrelated vendor's notarized app. Healthy Macs print "Notarized Developer ID".
"syspolicy_check distribution" reports a notary error, and "codesign -R="notarized" --check-notarization" fails.
RULED OUT
The stapled ticket (Contents/CodeResources, 1716 bytes, SHA-256 e8679543f9934bd43b127210c10348f764b78a53360ec515ccbcb4afc0920e28) is byte-identical on the affected Mac, on a healthy Mac, and in the official 9.5.1 package.
The network: TLS to api.apple-cloudkit.com and valid.apple.com works, there's no proxy, and the clock is correct (sntp offset 0.03 s).
WHAT A HEALTHY MAC DOES (fresh macOS 26.6.2 VM, app without quarantine)
Running the app's binary produces: "Extracting ticket from bundle" -> "Registering stapled ticket with system" -> CloudKit fetch -> "Inserting ticket". /var/db/SystemPolicyConfiguration/Tickets gains rows in the "tickets" and "hashes" tables, including the extension's cdhash. sysextd then validates the extension locally ("isNotarized = 1"), so the extension's notarization is established through the host app's ticket.
If I truncate CodeResources on the VM, I get the same "Unable to parse ticket" / "-1" lines and then -67050. So on the affected Mac, ticket registration seems to fail even though the ticket file is intact.
A third-party write-up describes the same signature on one Mac ("stapler validate" exit 65 for every vendor's app):
https://github.com/fsnow/cst/blob/main/docs/implementation/NOTARIZATION_TICKET_ISSUE.md
They report that none of these helped: resetting the Tickets database with SIP off, restarting syspolicyd/trustd, a fresh user account, or OS upgrades up to macOS 27.0.1.
QUESTIONS
What can make syspolicyd fail to parse or register a valid stapled ticket on a single Mac?
Is there a supported way to repair ticket registration without erasing the Mac?
Is it expected that sysextd validates nested code (the extension) only against the local ticket database, with no online fallback?
What should we collect for you: a sysdiagnose, or a Feedback Assistant report? [FB number if filed]