CVE-2026-39979
ADVISORY - ubuntuSummary
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 error construction logic performs an out-of-bounds read past the end of the buffer. The vulnerability is reachable by any libjq consumer calling jv_parse_sized() with untrusted input, and depending on memory layout, can result in memory disclosure or process termination. The issue has been patched in commit 2f09060afab23fe9390cce7cb860b10416e1bf5f.
Common Weakness Enumeration (CWE)
Out-of-bounds Read
Out-of-bounds Read
Ubuntu
3.9
CVSS SCORE
6.5medium| Package | Type | OS Name | OS Version | Affected Ranges | Fix Versions |
|---|---|---|---|---|---|
| ubuntu/jq | deb | ubuntu | 24.04 | <1.7.1-3ubuntu0.24.04.2 | 1.7.1-3ubuntu0.24.04.2 |
| ubuntu/jq | deb | ubuntu | 22.04 | <1.6-2.1ubuntu3.2 | 1.6-2.1ubuntu3.2 |
CVSS:3 Severity and metrics
The CVSS metrics represent different qualitative aspects of a vulnerability that impact the overall score, as defined by the CVSS Specification.
The vulnerable component is bound to the network stack, but the attack is limited at the protocol level to a logically adjacent topology. This can mean an attack must be launched from the same shared physical (e.g., Bluetooth or IEEE 802.11) or logical (e.g., local IP subnet) network, or from within a secure or otherwise limited administrative domain (e.g., MPLS, secure VPN to an administrative network zone). One example of an Adjacent attack would be an ARP (IPv4) or neighbor discovery (IPv6) flood leading to a denial of service on the local LAN segment (e.g., CVE-2013-6014).
Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success when attacking the vulnerable component.
The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
The vulnerable system can be exploited without interaction from any user.
An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
There is no loss of trust or accuracy within the impacted component.
Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.
NIST
3.9
CVSS SCORE
6.9mediumAlpine
-
Debian
-
Alma
-
CVSS SCORE
N/AhighAlma
-
CVSS SCORE
N/AhighAlma
-
CVSS SCORE
N/AhighRed Hat
3.9
CVSS SCORE
8.2highRocky
-
CVSS SCORE
N/AhighRocky
-
CVSS SCORE
N/AhighRocky
-
CVSS SCORE
N/AhighRocky
-
CVSS SCORE
N/AhighRocky
-
CVSS SCORE
N/AhighOracle
-
CVSS SCORE
N/AhighOracle
-
CVSS SCORE
N/AhighOracle
-
CVSS SCORE
N/AhighPhoton
CVE-2026-39979
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