PatchTheCVECVE-2026-39979: jq is a command-line JSON processor
49
This week
MEDIUM 6.5REMOTEWATCHLISTUPGRADEUPGRADEDOWNGRADE
CVE-2026-39979 is a medium-severity flaw (CVSS 6.5) affecting jq, ai inference server, ansible automation platform. 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 commits before 2f09060afab23fe9390cce7cb860b10416e1bf5f, the jv_parse_sized() API in libjq accepts a counted buffer with an explicit length parameter, but its error-handling path formats the input buffer using %s in jv_string_fmt(), which reads until a NUL terminator is found rather than respecting the caller-supplied length. This means that when malformed JSON is passed in a non-NUL-terminated buffer, the
Why this priority
- Public exploit reference
- Remotely exploitable, no login, no user action
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 6.5 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.6% (top 54%) |
| CISA exploited list | No |
| Weakness | CWE-125 |
| Published | 2026-04-13 |
| Last modified | 2026-10-26 |
Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
jqlang jq UPGRADE
Affected: < 1.8.2
Fixed in: 1.8.2
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy jq || rpm -q jq || jq --version
2. UPGRADE to 1.8.2 (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.
redhat ai inference server UPGRADE
Affected: >= 3.2.0 and < 3.2.2 · >= 3.3.0 and < 3.3.5
Fixed in: 3.2.2, 3.3.5
Safe to downgrade to: a release before 3.2.0
1. Check installed version
apt-cache policy ai-inference-server || rpm -q ai-inference-server || ai-inference-server --version
2. UPGRADE to 3.2.2 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade ai-inference-server
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade ai-inference-server
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before 3.2.0 (Debian / Ubuntu)
apt-cache madison ai-inference-server
sudo apt install ai-inference-server=<VERSION_BEFORE_3.2.0>
sudo apt-mark hold ai-inference-server
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list ai-inference-server
sudo dnf downgrade ai-inference-server-<VERSION_BEFORE_3.2.0>
sudo dnf versionlock add ai-inference-server
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
redhat ansible automation platform DOWNGRADE
Affected: 2.0
Fixed in: no fixed release known
Safe to downgrade to: a release before 2.0
1. Check installed version
apt-cache policy ansible-automation-platform || rpm -q ansible-automation-platform || ansible-automation-platform --version
2. No fixed release: DOWNGRADE to a release before 2.0 (Debian / Ubuntu)
apt-cache madison ansible-automation-platform
sudo apt install ansible-automation-platform=<VERSION_BEFORE_2.0>
sudo apt-mark hold ansible-automation-platform
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list ansible-automation-platform
sudo dnf downgrade ansible-automation-platform-<VERSION_BEFORE_2.0>
sudo dnf versionlock add ansible-automation-platform
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
redhat ceph storage DOWNGRADE
Affected: 4.0
Fixed in: no fixed release known
Safe to downgrade to: a release before 4.0
1. Check installed version
apt-cache policy ceph-storage || rpm -q ceph-storage || ceph-storage --version
2. No fixed release: DOWNGRADE to a release before 4.0 (Debian / Ubuntu)
apt-cache madison ceph-storage
sudo apt install ceph-storage=<VERSION_BEFORE_4.0>
sudo apt-mark hold ceph-storage
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list ceph-storage
sudo dnf downgrade ceph-storage-<VERSION_BEFORE_4.0>
sudo dnf versionlock add ceph-storage
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
redhat codeready linux builder DOWNGRADE
Affected: 8.0 · 9.0 · 10.0
Fixed in: no fixed release known
Safe to downgrade to: a release before 8.0
1. Check installed version
apt-cache policy codeready-linux-builder || rpm -q codeready-linux-builder || codeready-linux-builder --version
2. No fixed release: DOWNGRADE to a release before 8.0 (Debian / Ubuntu)
apt-cache madison codeready-linux-builder
sudo apt install codeready-linux-builder=<VERSION_BEFORE_8.0>
sudo apt-mark hold codeready-linux-builder
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list codeready-linux-builder
sudo dnf downgrade codeready-linux-builder-<VERSION_BEFORE_8.0>
sudo dnf versionlock add codeready-linux-builder
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
redhat codeready linux builder eus DOWNGRADE
Affected: 9.4 · 9.6 · 10.0
Fixed in: no fixed release known
Safe to downgrade to: a release before 9.4
1. Check installed version
apt-cache policy codeready-linux-builder-eus || rpm -q codeready-linux-builder-eus || codeready-linux-builder-eus --version
2. No fixed release: DOWNGRADE to a release before 9.4 (Debian / Ubuntu)
apt-cache madison codeready-linux-builder-eus
sudo apt install codeready-linux-builder-eus=<VERSION_BEFORE_9.4>
sudo apt-mark hold codeready-linux-builder-eus
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list codeready-linux-builder-eus
sudo dnf downgrade codeready-linux-builder-eus-<VERSION_BEFORE_9.4>
sudo dnf versionlock add codeready-linux-builder-eus
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
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.
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-2026-39979?
jq: upgrade to 1.8.2; ai inference server: upgrade to 3.2.2, 3.3.5; ansible automation platform: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2026-39979 being exploited?
CVE-2026-39979 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-2026-39979 affect?
CVE-2026-39979 affects jq, ai inference server, ansible automation platform. Severity is medium (CVSS 6.5). jq is a command-line JSON processor. In commits before 2f09060afab23fe9390cce7cb860b10416e1bf5f, the jv_parse_sized() API in libjq accepts a counted buffer with an explicit length parameter, but its error-handling path formats the input buf
How urgent is CVE-2026-39979?
Priority 49/100. Public exploit reference; Remotely exploitable, no login, no user action; On your watchlist
Software pages
Ansible vulnerabilities · Ceph vulnerabilities
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