Out-of-bounds Read in Amazon Ion-C

CVE-2025-12829

An uninitialized stack read issue exists in Amazon Ion-C versions <v1.1.4 that may allow a threat actor to craft data and serialize it to Ion text in such a way that sensitive data in memory could be exposed through UTF-8 escape sequences. To mitigate this issue, users should upgrade to version v1.1.4.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.2 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.002 (3.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 4th percentile — 3.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-12829: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-12829?
CVE-2025-12829 is a medium-severity vulnerability in Amazon Ion-C, classified under Out-of-bounds Read. CVSS score: 6.2/10. Published 2025-11-07.
How severe is CVE-2025-12829?
Medium severity. CVSS v3 base score is 6.2 out of 10.