CVE-2026-70634

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/timescale/timescaledb/commit/517c13e7cc6afadb4a7deaa7a5a5a29065e5b5a3	Patch
https://github.com/timescale/timescaledb/pull/10360	Issue Tracking Patch
https://www.vulncheck.com/advisories/timescaledb-out-of-bounds-read-information-disclosure-via-dictionary-compression-reverse-iterator	Patch Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:timescale:timescaledb:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-08-06 22:18

Updated : 2026-09-01 15:31

NVD link : CVE-2026-70634

Mitre link : CVE-2026-70634

CVE.ORG link : CVE-2026-70634

JSON object : View

Products Affected

timescale

timescaledb

CWE

CWE-125

Out-of-bounds Read

CWE-129

Improper Validation of Array Index

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