CVE-2026-49844
published 2026-07-10CVE-2026-49844: Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON. This…
PriorityP335medium5.9CVSS 3.1
AVNACHPRNUINSUCNIHAN
EPSS
0.60%
47.7th percentile
Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON. This issue affects Apache Log4j API versions 2.13.1 through 2.25.4 and version 2.26.0.
The fix for CVE-2026-34481 did not cover all code paths: when a MapMessage contains a non-finite IEEE 754 value (NaN, Infinity, or -Infinity), MapMessage.asJson() emits the corresponding bare token. RFC 8259 does not permit these tokens, so a conformant parser rejects the resulting document.
The defect is reachable only when both of the following conditions hold:
* The application uses the message resolver https://logging.apache.org/log4j/2.x/manual/json-template-layout.html#event-template-resolver-message of JsonTemplateLayout or any other layout that relies on MapMessage.asJson() or MapMessage.getFormattedMessage(new String[]{"JSON"}).
* The application logs a MapMessage that contains an attacker-controlled floating-point value.
An attacker who can supply a non-finite value can cause the affected layout to emit malformed JSON, which may corrupt the enclosing log record or disrupt downstream log ingestion and parsing.
Users are advised to upgrade to Apache Log4j API 2.25.5 or 2.26.1, both of which emit RFC 8259-compliant JSON for non-finite values.
Affected
52 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| apache | log4j | — | — |
| apache | log4j | — | — |
| apache | log4j | — | — |
| apache | log4j | — | — |
| apache | log4j | — | — |
| apache | log4j | — | — |
| apache | log4j | — | — |
| apache | log4j | >= 2.13.1 < 2.25.5 | 2.25.5 |
| apache | log4j | >= 2.14.0 < 2.25.4 | 2.25.4 |
| apache_software_foundation | apache_log4j_api | >= 2.13.1 < 2.25.5 | 2.25.5 |
| apache_software_foundation | apache_log4j_api | >= 2.26.0 < 2.26.1 | 2.26.1 |
| apache_software_foundation | apache_log4j_api | 3.0.0-alpha1 – 3.0.0-beta2 | — |
| devspaces | openvsx-rhel9 | — | — |
| devspaces | pluginregistry-rhel9 | — | — |
| eap74-els-openjdk11-openshift-rhel8 | eap74-els-openjdk11-openshift-rhel8 | — | — |
| eap74-els-openjdk17-openshift-rhel8 | eap74-els-openjdk17-openshift-rhel8 | — | — |
| eap74-els-openjdk8-openshift-rhel8 | eap74-els-openjdk8-openshift-rhel8 | — | — |
| jboss-eap-7-eap74-els-openjdk11-openshift-rhel8 | jboss-eap-7-eap74-els-openjdk11-openshift-rhel8 | — | — |
| jboss-eap-7-eap74-els-openjdk17-openshift-rhel8 | jboss-eap-7-eap74-els-openjdk17-openshift-rhel8 | — | — |
| offline-knowledge-portal | rhokp-rhel9 | — | — |
| openshift-serverless-1 | kn-eventing-integrations-aws-ddb-streams-source-rhel9 | — | — |
| openshift-serverless-1 | kn-eventing-integrations-aws-s3-sink-rhel9 | — | — |
| openshift-serverless-1 | kn-eventing-integrations-aws-s3-source-rhel9 | — | — |
| openshift-serverless-1 | kn-eventing-integrations-aws-sns-sink-rhel9 | — | — |
| openshift-serverless-1 | kn-eventing-integrations-aws-sqs-sink-rhel9 | — | — |
CVSS provenance
nvdv3.15.9MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
nvdv4.06.3MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
ghsa7.5HIGH
vendor_oracle9.9CRITICAL
vendor_redhat7.5HIGH
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GHSA
Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON.
ghsa_unreviewed·2026-07-11·CVSS 7.5
CVE-2026-49844 [HIGH] CWE-116 Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON.
Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON. This issue affects Apache Log4j API versions 2.13.1 through 2.25.4 and version 2.26.0.
The fix for CVE-2026-34481 did not cover all code paths: when a MapMessage contains a non-finite IEEE 754 value (NaN, Infinity, or -Infinity), MapMessage.asJson() emits the corresponding bare token. RFC 8259 does not permit these tokens, so a conformant parser rejects the resulting document.
The defect is reachable only when both of the following conditions hold:
* The application uses the message resolver https://logging.apache.org/log4j/2.x/manual/json-template-layout.html#event-template-resolver-message of JsonTemplateLayout or any other layout that
GHSA
Apache Log4j API: Improper encoding of non-finite floating-point values during MapMessage JSON serialization
ghsa·2026-07-11·CVSS 7.5
CVE-2026-49844 [HIGH] CWE-116 Apache Log4j API: Improper encoding of non-finite floating-point values during MapMessage JSON serialization
Apache Log4j API: Improper encoding of non-finite floating-point values during MapMessage JSON serialization
Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON. This issue affects Apache Log4j API versions 2.13.1 through 2.25.4 and version 2.26.0.
The fix for CVE-2026-34481 did not cover all code paths: when a MapMessage contains a non-finite IEEE 754 value (NaN, Infinity, or -Infinity), MapMessage.asJson() emits the corresponding bare token. RFC 8259 does not permit these tokens, so a conformant parser rejects the resulting document.
The defect is reachable only when both of the following conditions hold:
* The application uses the message resolver https://logging.apache.org/log4j/2.x/ma
VulDB
Apache Log4j API up to 2.25.4/2.26.0 MapMessage MapMessage.asJson encoding error
vuldb·2026-07-11·CVSS 6.3
CVE-2026-49844 [MEDIUM] Apache Log4j API up to 2.25.4/2.26.0 MapMessage MapMessage.asJson encoding error
A vulnerability, which was classified as critical, has been found in Apache Log4j API up to 2.25.4/2.26.0. Affected is the function MapMessage.asJson of the component MapMessage. The manipulation leads to encoding error.
This vulnerability is documented as CVE-2026-49844. The attack can be initiated remotely. There is not any exploit available.
Red Hat
org.apache.logging.log4j/log4j-api: Apache Log4j API: Malformed JSON output due to improper encoding of floating-point values
vendor_redhat·2026-07-10·CVSS 7.5
CVE-2026-49844 [HIGH] CWE-838 org.apache.logging.log4j/log4j-api: Apache Log4j API: Malformed JSON output due to improper encoding of floating-point values
org.apache.logging.log4j/log4j-api: Apache Log4j API: Malformed JSON output due to improper encoding of floating-point values
Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON. This issue affects Apache Log4j API versions 2.13.1 through 2.25.4 and version 2.26.0.
The fix for CVE-2026-34481 did not cover all code paths: when a MapMessage contains a non-finite IEEE 754 value (NaN, Infinity, or -Infinity), MapMessage.asJson() emits the corresponding bare token. RFC 8259 does not permit these tokens, so a conformant parser rejects the resulting document.
The defect is reachable only when both of the following conditions hold:
* The application uses the message resolver https://logging.apache.or
Oracle
Oracle Oracle Communications Risk Matrix: Infrastructure (valkey) — CVE-2025-49844
vendor_oracle·2026-01-15·CVSS 9.9
CVE-2025-49844 [CRITICAL] Oracle Oracle Communications Risk Matrix: Infrastructure (valkey) — CVE-2025-49844
Oracle Oracle Communications Risk Matrix: Infrastructure (valkey) vulnerability
CVE: CVE-2025-49844
CVSS: 9.9
Protocol: HTTP
Remote exploit: No
Affected versions: Network
Advisory: cpujan2026 (JAN 2026)
No detection rules found.
No public exploits indexed.
2026-07-10
Published