CVE-2026-84851 json
Uncontrolled recursion in the Ion reader in Amazon Ion-C before 1.1.6
published 2mo ago modified 2mo ago also EUVD-2026-70281 , GHSA-9gfg-hgj4-gh44
Unreviewed: the maintainers' own advisory
Published by the maintainers on their GitHub repository amazon-ion/ion-c. GitHub has not reviewed it into the GitHub Advisory Database, so the affected packages and versions are the maintainers' word. Read the full advisory on GitHub.
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 49%
- public exploits
- 0
- none known
Summary
An uncontrolled recursion issue exists in Amazon Ion-C versions before 1.1.6 that might allow a remote unauthenticated actor to craft Ion data that exhausts the native call stack and crashes the application using the library, resulting in a denial of service.
Patch / fix
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 2mo ago
Exploit prediction
0.61% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- Amazon ion-c
Classification
- Weakness
-
- CWE-674 Uncontrolled Recursion
References
-
github.com
/amazon-ion/ion-c/releases/tag/v1.1.6
release-notes, patch
-
aws.amazon.com
/security/security-bulletins/2026-094-aws/
vendor-advisory
-
github.com
/amazon-ion/ion-c/security/advisories/GHSA-9gfg-hgj4-gh44
release-notes, advisory
Sources
- CVE List CVE-2026-84851
- NVD CVE-2026-84851
- Maintainer advisory GHSA-9gfg-hgj4-gh44
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
The maintainers of amazon-ion/ion-c published their own advisory on GitHub. Reviewed sources take precedence over it.