luben zstd-jni up to 1.5.7-13 setDict/setLongMax/setLevel/setRefMultipleDDicts use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.3$0-$5k1.40+

Summaryinfo

A vulnerability categorized as critical has been discovered in luben zstd-jni up to 1.5.7-13. Impacted is the function setDict/setLongMax/setLevel/setRefMultipleDDicts. Such manipulation leads to use after free. This vulnerability is referenced as CVE-2026-87877. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in luben zstd-jni up to 1.5.7-13. Affected by this issue is the function setDict/setLongMax/setLevel/setRefMultipleDDicts. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. CVE summarizes:

zstd-jni versions before 1.5.7-14 fail to validate closed state in setDict, setLongMax, setLevel and setRefMultipleDDicts methods of stream classes. Attackers can call these methods on closed streams to write through freed native pointers, corrupting unrelated objects or crashing the JVM.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-87877 since 09/09/2026. The exploitation is known to be easy. The attack may be launched remotely. There are known technical details, but no exploit is available.

Upgrading to version 1.5.7-14 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.7
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: zstd-jni 1.5.7-14

Timelineinfo

09/09/2026 Advisory disclosed
09/09/2026 +0 days CVE reserved
09/09/2026 +0 days VulDB entry created
09/09/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-87877 (🔒)
GCVE (CVE): GCVE-0-2026-87877
GCVE (VulDB): GCVE-100-401780

Entryinfo

Created: 09/09/2026 16:59
Changes: 09/09/2026 16:59 (76)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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