github.com/buger/jsonparser: Improper Validation of Array Index
CVE-2026-32285 is a high-severity improper validation of array index vulnerability in github.com/buger/jsonparser, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 1.1.2 as the first without the flaw, so updating github.com/buger/jsonparser to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.8% chance of exploitation within 30 days, higher than 57% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update github.com/buger/jsonparser to 1.1.2 or a later version.
- Update Jsonparser to 1.1.2 or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.5 | High | CISA (ADP) |
| CVSS 3.1 | 7.5 | High | CNA |
Official description
The Delete function fails to properly validate offsets when processing malformed JSON input. This can lead to a negative slice index and a runtime panic, allowing a denial of service attack.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Validation of Array Index
The product uses untrusted input when calculating or using an array index, but the product does not validate or incorrectly validates the index to ensure the index references a valid position within the array.
How developers prevent this class of flaw
- Use an input validation framework such as Struts or the OWASP ESAPI Validation API. Note that using a framework does not automatically address all input validation problems; be mindful of weaknesses that could arise from misusing the framework itself (CWE-1173).
- Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, Ada allows the programmer to constrain the values of a variable and languages such as Java and Ruby will allow the programmer to handle exceptions when an out-of-bounds index is accessed.
- Use a CPU and operating system that offers Data Execution Protection (using hardware NX or XD bits) or the equivalent techniques that simulate this feature in software, such as PaX. These techniques ensure that any instruction executed is exclusively at a memory address that is part of the code segment. For more information on these techniques see D3-PSEP (Process Segment Execution Prevention) from D3FEND.
More Improper Validation of Array Index vulnerabilities (CWE-129)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- github.com/buger/jsonparser/issues/275Issue Tracking, Third Party Advisory
- github.com/golang/vulndb/issues/4514Issue Tracking, Third Party Advisory
- pkg.go.dev/vuln/GO-2026-4514Third Party Advisory
Technical write-ups (may include proof of concept)
- securityinfinity.com/research/buger-jsonparser-negative-slice-panic-dos-2026Exploit, Third Party Advisory
Other references
- access.redhat.com/errata/RHSA-2026:13548
- access.redhat.com/errata/RHSA-2026:17121
- access.redhat.com/errata/RHSA-2026:17123
- access.redhat.com/errata/RHSA-2026:19099
- access.redhat.com/errata/RHSA-2026:21769
- access.redhat.com/errata/RHSA-2026:22347
- access.redhat.com/errata/RHSA-2026:22423
- access.redhat.com/errata/RHSA-2026:23345
- access.redhat.com/errata/RHSA-2026:34364
- access.redhat.com/errata/RHSA-2026:35111
- access.redhat.com/errata/RHSA-2026:36882
- access.redhat.com/errata/RHSA-2026:61314
- access.redhat.com/errata/RHSA-2026:7191
- access.redhat.com/errata/RHSA-2026:9385
- access.redhat.com/security/cve/CVE-2026-32285
Recent Improper Validation of Array Index vulnerabilities
- 7.5 High severity
- 7.8 High severity
- 7.5 High severity
- 8.8 High severity
- 8.8 High severity
- 7.5 High severity
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