CVE-2026-49839: jq --rawfile invalid-state reuse after String too long causes heap-buffer-overflow
Vulnerability summary
CVE-2026-49839 is a high (CVSS 7.1) Out-of-bounds Write vulnerability in jqlang jq. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 5.7% of scored vulnerabilities. 1 public exploit is recorded.
Public exploit (GitHub, Date unknown)
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 9 · Related 7Timeline
- 25-06-2026PublishedVulnerability first disclosed.
- 25-06-2026Last modifiedVulnerability information updated.
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 metrics
5 scores · 5 sources · 1 version- OSV · AlpineEcosystem advisory · calculated7.1HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
- OSV · UbuntuEcosystem advisory · calculated7.1HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.1HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
- NVDNIST7.1HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
EPSS trend
Probability
0.17%
Chance of exploitation in the next 30 days
Percentile
6%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.17% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
1 foundJq
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.
Alpine1 product
- jq< 1.8.2-r0
Debian1 product
- jq< 1.6-2.1+deb12u2 | < 1.7.1-6+deb13u3 | < 1.8.1-8
Jqlang1 product
- jq< 1.8.2
Ubuntu1 product
- jqAll versions (No fix recorded)
4 vendors · 4 products
References
6 links- github.com/jqlang/jq/security/advisories/GHSA-cfh2-vwfq-qfmmX Refsource CONFIRMREPORTExploitVendor Advisory
