High severity · published Sep 9, 2026
CVE-2026-87877
zstd-jni 1.3.8-4 through 1.5.7-13 Use-After-Free via Setters Called After close()
7.7
CVSS
0.2%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 13% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZS
zstd-jni · luben
1.3.8-4 before 1.5.7-14 · source: vendor