Vulnerability Description
jq is a command-line JSON processor. Prior to 1.8.2,` jq --rawfile` can turn a handled oversized-string error into invalid-state reuse and a real heap out-of-bounds write in assertion-disabled builds. When jv_load_file(raw=1) reads an attacker-controlled file, it repeatedly appends file chunks to the same jv string accumulator. Once jv_string_append_buf() returns jv_invalid_with_msg("String too long"), the raw-file loop does not stop. If the file contains at least one more byte, the next loop iteration appends a new chunk to an object that is already invalid. With assertions enabled this aborts in jvp_string_ptr(). With assertions disabled, the invalid object is interpreted as a string object and ASan reports heap-buffer-overflow. This vulnerability is fixed in 1.8.2.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Jqlang | Jq | < 1.8.2 |
Related Weaknesses (CWE)
References
- https://github.com/jqlang/jq/security/advisories/GHSA-cfh2-vwfq-qfmmExploitVendor Advisory
- https://github.com/jqlang/jq/security/advisories/GHSA-cfh2-vwfq-qfmmExploitVendor Advisory
FAQ
What is CVE-2026-49839?
CVE-2026-49839 is a vulnerability with a CVSS score of 7.1 (HIGH). jq is a command-line JSON processor. Prior to 1.8.2,` jq --rawfile` can turn a handled oversized-string error into invalid-state reuse and a real heap out-of-bounds write in assertion-disabled builds....
How severe is CVE-2026-49839?
CVE-2026-49839 has been rated HIGH with a CVSS base score of 7.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-49839?
Check the references section above for vendor advisories and patch information. Affected products include: Jqlang Jq.