jq: Embedded NUL truncates top-level jq programs loaded with -f
Key facts
- Attack vector
- Local
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Partial Red Hat: 1 fixed, 6 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
jq is a command-line JSON processor. In 1.8.1 and earlier, Top-level jq programs loaded from a file with -f are truncated at the first embedded NUL byte on current upstream HEAD. A crafted filter file such as . followed by \x00 and arbitrary suffix compiles and executes as only the prefix before the NUL. This leaves jq with a post-CVE-2026-33948 prefix/full-buffer mismatch on the compilation path even though the JSON parser path has already been fixed.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Red Hat 1 advisory
- RHSA-2026:29986 Released 2026-06-25 · Red Hat rating ModerateRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images jq-1.8.2-0.1.hum1@aarch64, jq-1.8.2-0.1.hum1@src, jq-1.8.2-0.1.hum1@x86_64 +2
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Ansible Automation Platform 2 | Affected | No fix yet: Fix deferred |
| Red Hat Ceph Storage 4 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat Hardened Images | Fixed | RHSA-2026:29986 |
Timeline
- 2026-10-02 Threatist record created from CVE-2026-41256
References
More jqlang Jq vulnerabilities
- TI-2026-24844 jq: Integer overflow in jvp_string_append() allows Heap-based Buffer Overflow CVSS 3.1HIGH 8.2
- TI-2025-30431 AddressSanitizer: stack-buffer-overflow in jq_fuzz_execute (jv_string_vfmt) CVSS 4.0HIGH 7.7
- TI-2023-26962 decToString in decNumber/decNumber.c in jq 88f01a7 has a one-byte out-of-bounds write via… CVSS 3.1HIGH 7.5
- TI-2026-28834 jq: Out-of-Bounds Read in jv_parse_sized() Error Formatting for Non-NUL-Terminated Counted Buffers CVSS 4.0MEDIUM 6.9
- TI-2024-35799 Type confusion in jqlang jq CVSS 3.1HIGH 8.1
- TI-2026-36743 jq --rawfile invalid-state reuse after String too long causes heap-buffer-overflow CVSS 3.1HIGH 7.1
Sources
- CVE-2026-41256 · CVE Program
- CVE-2026-41256 · NVD
- FIRST EPSS
- CVE-2026-41256 · Red Hat security data · CC BY 4.0
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