CVE-2026-41257: jq is a command-line JSON processor

Q: How do I fix CVE-2026-41257?

jq: upgrade to newer than 1.8.1. Exact commands for each OS are on this page.

Q: Is CVE-2026-41257 being exploited?

CVE-2026-41257 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-41257 affect?

CVE-2026-41257 affects jq. Severity is medium (CVSS 5.5). jq is a command-line JSON processor. In 1.8.1 and earlier, the jq bytecode VM's data stack tracks its allocation size in a signed int. When the stack grows beyond ≈1 GiB (via deeply nested generator forks), the doubling arithmetic overflows

Q: How urgent is CVE-2026-41257?

Priority 25/100. Public exploit reference

Routine

MEDIUM 5.5UPGRADE

CVE-2026-41257 is a medium-severity flaw (CVSS 5.5) affecting jq. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

jq is a command-line JSON processor. In 1.8.1 and earlier, the jq bytecode VM's data stack tracks its allocation size in a signed int. When the stack grows beyond ≈1 GiB (via deeply nested generator forks), the doubling arithmetic overflows. The wrapped value is passed to realloc and then used for a memmove with attacker-influenced offsets.

Why this priority

Public exploit reference

A fixed release or distro patch exists.

Risk facts

CVSS score	5.5 (Medium)
Attack vector	Local
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	0.1% (top 97%)
CISA exploited list	No
Weakness	CWE-190, CWE-787
Published	2026-05-11
Last modified	2026-10-26

Publisher (CNA): GitHub, Inc. · Vendor: jqlang

Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-05-11 18:16 UTCPublished CVE record published
2026-10-26 18:10 UTCUpdated Record last modified

jqlang jq UPGRADE

Affected: <= 1.8.1

Fixed in: newer than 1.8.1

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy jq || rpm -q jq || jq --version

2. UPGRADE to newer than 1.8.1 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade jq

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade jq

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-41257?

jq: upgrade to newer than 1.8.1. Exact commands for each OS are on this page.

Is CVE-2026-41257 being exploited?

CVE-2026-41257 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-41257 affect?

CVE-2026-41257 affects jq. Severity is medium (CVSS 5.5). jq is a command-line JSON processor. In 1.8.1 and earlier, the jq bytecode VM's data stack tracks its allocation size in a signed int. When the stack grows beyond ≈1 GiB (via deeply nested generator forks), the doubling arithmetic overflows

How urgent is CVE-2026-41257?

Priority 25/100. Public exploit reference

Related CVEs

CVE-2026-32316 HIGH 8.2 UPGRADE jq is a command-line JSON processor
CVE-2026-39979 MEDIUM 6.5 UPGRADE UPGRADE jq is a command-line JSON processor
CVE-2026-33948 MEDIUM 5.3 UPGRADE jq is a command-line JSON processor
CVE-2026-33947 MEDIUM 6.2 UPGRADE jq is a command-line JSON processor
CVE-2026-39956 MEDIUM 6.1 UPGRADE jq is a command-line JSON processor

References

← Back to latest CVEs