Vulnerability · Published Oct 15, 2026 · Assigned by GitHub_M

CVE-2026-97370Junrar: RarVM VM_JMP maxOpCount bypass causes infinite CPU loop during RAR4 extraction

High 7.5

In plain English

A high-severity infinite loop in junrar from junrar. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 35% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.4%top 65.3% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Junrar is an open source Java RAR archive library. Prior to 7.6.1, RarVM.ExecuteCode in src/main/java/com/github/junrar/unpack/vm/RarVM.java can repeatedly execute a VM_JMP instruction whose target is greater than or equal to the prepared program's codeSize. The setIP() function returns success without changing the instruction pointer or decrementing maxOpCount, and the jump handler continues before loop-end accounting, leaving both values unchanged. A crafted RAR4 archive can therefore keep an extraction thread in an infinite CPU loop and exhaust archive-processing worker capacity. The RAR virtual machine does not expose native process execution, so the supported impact is availability loss rather than code execution. This issue is fixed in version 7.6.1.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Maven	com.github.junrar:junrar	7.6.1	GHSA-h9h9-2rmf-rvhp

Affected products (as reported)

Vendor	Product	Versions
junrar	junrar	< 7.6.1

Weakness: CWE-835 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

https://github.com/junrar/junrar/security/advisories/GHSA-h9h9-2rmf-rvhp x_refsource_CONFIRM
https://github.com/junrar/junrar/commit/687a09c42f46066447faa9179ee11314ad6d9afb x_refsource_MISC
https://github.com/junrar/junrar/releases/tag/v7.6.1 x_refsource_MISC