chore(deps): update consensys/teku docker tag to v26.3.0

[renovate]

This PR contains the following updates:

Package	Update	Change
consensys/teku (source)	minor	26.2.0 → 26.3.0

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Release Notes

Consensys/teku (consensys/teku)

v26.3.0

Compare Source

This is a mandatory update containing the fix for recent mainnet beacon state serialization issue as well as performance improvements and library updates.

The mainnet issue is showing in logs as the following error:

2026-03-05 16:16:26.201 ERROR - Storage update failed, retrying.
java.util.concurrent.CompletionException: java.lang.NegativeArraySizeException: -215782466
at java.base/java.util.concurrent.CompletableFuture.wrapInCompletionException(Unknown Source)
at java.base/java.util.concurrent.CompletableFuture.reportJoin(Unknown Source)
at java.base/java.util.concurrent.CompletableFuture.join(Unknown Source)
at tech.pegasys.teku.storage.server.RetryingStorageUpdateChannel.retry(RetryingStorageUpdateChannel.java:133)
at tech.pegasys.teku.storage.server.RetryingStorageUpdateChannel.onStorageUpdate(RetryingStorageUpdateChannel.java:86)
at tech.pegasys.teku.storage.server.CombinedStorageChannelSplitter.onStorageUpdate(CombinedStorageChannelSplitter.java:71)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(Unknown Source)
at java.base/java.lang.reflect.Method.invoke(Unknown Source)
...

Downloads

• Available as 26.3.0 on Dockerhub
• Download the binary distribution:
  • tar.gz (sha256: 2852f622bcc5064d6e2da5bc2cd852477fa9ca179ab565d3303043c26bfbc0ae)
  • zip (sha256: c34c8e39c5efc33cb7cb9cb0e1f8ffdcb57aee6c1cde4fc80a995b68da233978)

Additions and Improvements

• Use jemalloc in our docker images to improve memory allocation
• Nodes with >50% custody requirements will be able to import blocks after downloading 50% of the sidecars, and the remaining sidecars will be handled as a background task. This includes nodes servicing validators in excess of 2048 eth effective balance, as well as voluntary supernodes.

Bug Fixes

• fixed SSZ serialization bug causing an integer overflow while calculating ssz size.
• fixed an issue with dependent root calculation which was causing future epoch block proposal duties to be recalculated.
• fixed v1 proposer duties returning incompatible roots for the v1 endpoint (should be compatible with pre-fulu dependent roots).

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