Bug 2521838

Summary: CVE-2026-70634 timescaledb: TimescaleDB: Information disclosure via out-of-bounds read in dictionary compression. [epel-all]
Product: [Fedora] Fedora EPEL Reporter: Vladimir Vasilev <vvasilev>
Component: timescaledbAssignee: Filip Januš <fjanus>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: epel10CC: aurelien, db-sig, fjanus
Target Milestone: ---Keywords: Security, SecurityTracking
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Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["e5d7b840-1a4b-453c-a0e3-cd969b42f329"]}
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On:    
Bug Blocks: 2512304    

Description Vladimir Vasilev 2026-08-24 12:36:28 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

TimescaleDB through 2.29.1, fixed in commit 517c13e, contains an out-of-bounds read in the Dictionary compression reverse row iterator (tsl/src/compression/algorithms/dictionary.c). The forward path validates the decoded index; the reverse path uses an assertion compiled out of release builds, leaving the 64-bit Simple8b index unvalidated and the read offset attacker-controlled. Attackers with DML access to a physical compressed relation can store a crafted datum and run a reverse-order scan. With a pass-by-value column type the out-of-bounds Datum is returned to the client as a normal column value, disclosing backend memory including the shared buffer pool, which SQL access control does not cover.