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NVD / CVE Program· CNA GitHub_M

CVE-2026-33948: jq: Embedded-NUL Truncation in CLI JSON Input Path Causes Prefix-Only Validation of Malformed Input

LowCVSS 2.9 · v4.0—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 11/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.26% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: azl3 jq 1.7.1-4 on Azure Linux 3.0 1.7.1-5; cbl2 jq 1.6-5 on CBL Mariner 2.0 1.6-6; cbl2 jq 1.6-5 on CBL-Mariner 2.0 1.6-6.

Low priority for now. Upgrade to azl3 jq 1.7.1-4 on Azure Linux 3.0 1.7.1-5; cbl2 jq 1.6-5 on CBL Mariner 2.0 1.6-6; cbl2 jq 1.6-5 on CBL-Mariner 2.0 1.6-6 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

jq is a command-line JSON processor. Commits before 6374ae0bcdfe33a18eb0ae6db28493b1f34a0a5b contain a vulnerability where CLI input parsing allows validation bypass via embedded NUL bytes. When reading JSON from files or stdin, jq uses strlen() to determine buffer length instead of the actual byte count from fgets(), causing it to truncate input at the first NUL byte and parse only the preceding prefix. This enables an attacker to craft input with a benign JSON prefix before a NUL byte followed by malicious trailing data, where jq validates only the prefix as valid JSON while silently discarding the suffix. Workflows relying on jq to validate untrusted JSON before forwarding it to downstream consumers are susceptible to parser differential attacks, as those consumers may process the full input including the malicious trailing bytes. This issue has been patched by commit 6374ae0bcdfe33a18eb0ae6db28493b1f34a0a5b.

Published
Apr 14, 2026
Updated
Oct 26, 2026
EPSS
0.2% · 18th percentile

Report tools

JSON

Action score

11

Monitor

Low priority for now.

CVSS
11 / 40 · 2.9 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
2.9
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-33948

When you'll hear from us

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  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
jqlangjq

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • jqlang jq

    • < 6374ae0bcdfe33a18eb0ae6db28493b1f34a0a5baffected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • jqlang jqbefore 1.8.2

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Alpine:v3.22jqbefore 1.8.2-r01.8.2-r0
Debian:12jqbefore 1.6-2.1+deb12u21.6-2.1+deb12u2
Debian:13jqbefore 1.7.1-6+deb13u21.7.1-6+deb13u2
Debian:14jqbefore 1.8.1-51.8.1-5
openSUSE:Leap 16.0jqbefore 1.7.1-160000.3.11.7.1-160000.3.1
openSUSE:Tumbleweedjqbefore 1.8.1-3.11.8.1-3.1
Red Hat:hummingbird:1jqbefore 0:1.8.1-3.hum10:1.8.1-3.hum1
Red Hat:hummingbird:1jq-develbefore 0:1.8.1-3.hum10:1.8.1-3.hum1
SUSE:Linux Enterprise Micro 5.3jqbefore 1.7.1-150000.3.25.11.7.1-150000.3.25.1
SUSE:Linux Micro 6.0jqbefore 1.6-6.11.6-6.1
SUSE:Linux Micro 6.0jqbefore 1.7.1-1.11.7.1-1.1
SUSE:Linux Micro 6.1jqbefore 1.7.1-slfo.1.1_3.11.7.1-slfo.1.1_3.1
SUSE:Linux Micro 6.2jqbefore 1.7.1-160000.3.11.7.1-160000.3.1

Same product

jqlang: all records

Other highest-scoring records for the same primary product.

  • CVE-2024-53427decNumberCopy in decNumber.c in jq through 1.7.1 does not properly consider that NaN is interpreted as numeric, which has a resultant…
    32Monitor
  • CVE-2026-40164jq: Algorithmic complexity DoS via hardcoded MurmurHash3 seed
    30Monitor
  • CVE-2026-32316jq: Integer overflow in jvp_string_append() allows Heap-based Buffer Overflow
    30Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-39956Apr 13, 2026 · jq: Missing runtime type checks for _strindices lead to crash and limited memory disclosure
    24Monitor
  • ← EarlierCVE-2026-39979Apr 13, 2026 · jq: Out-of-Bounds Read in jv_parse_sized() Error Formatting for Non-NUL-Terminated Counted Buffers
    27Monitor
  • Later →CVE-2026-40612May 11, 2026 · jq: Stack overflow via unbounded recursion in jv_contains
    21Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
azl3 jq 1.7.1-4 on Azure Linux 3.01.7.1-5 · CBL-Mariner ReleasesMicrosoft (MSRC)
cbl2 jq 1.6-5 on CBL Mariner 2.01.6-6 · CBL-Mariner ReleasesMicrosoft (MSRC)
cbl2 jq 1.6-5 on CBL-Mariner 2.01.6-6 · Release NotesMicrosoft (MSRC)
alpine:jq1.8.2-r0 · Alpine:v3.22Package registry (OSV)
debian:jq1.6-2.1+deb12u2 · Debian:12Package registry (OSV)
opensuse:jq1.8.1-3.1 · openSUSE:TumbleweedPackage registry (OSV)
red hat:jq0:1.8.1-3.hum1 · Red Hat:hummingbird:1Package registry (OSV)
red hat:jq-devel0:1.8.1-3.hum1 · Red Hat:hummingbird:1Package registry (OSV)
suse:jq1.7.1-160000.3.1 · SUSE:Linux Micro 6.2Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-4389527 days apartjq: Embedded NUL in jq import paths causes local redaction-policy bypass and preserves sensitive fields in published artifacts
    17Monitor

Not on record for this CVE: EPSS history · researcher credit · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-20 · Improper Input Validation

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/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

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

References

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records