Out-of-bounds Read in Timescale Timescaledb
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H.
EPSS exploit prediction
EPSS: 0.005 (45.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 45th percentile — 45.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
- Timescale Timescaledb — versions 0, 517c13e7cc6afadb4a7deaa7a5a5a29065e5b5a3
Weakness classification (CWE)
References
- github.com/timescale/timescaledb/commit/517c13e7cc6afadb4a7deaa7a5a5a29065e5b5a3 (Patch, patch)
- github.com/timescale/timescaledb/pull/10360 (issue-tracking, Patch, Issue Tracking)
- www.vulncheck.com/advisories/timescaledb-out-of-bounds-read-information-disclos… (Patch, Third Party Advisory, third-party-advisory)
Frequently asked questions
- What is CVE-2026-70634?
- CVE-2026-70634 is a high-severity vulnerability in Timescale Timescaledb, classified under Out-of-bounds Read. CVSS score: 8.1/10. Published 2026-08-06.
- How severe is CVE-2026-70634?
- High severity. CVSS v3 base score is 8.1 out of 10.