Out-of-bounds Read in Ning Compress-Lzf
CVE-2026-109395
Ning compress-lzf before 1.2.0 contains an out-of-bounds memory access vulnerability in the sun.misc.Unsafe based UnsafeChunkDecoder that fails to validate back-references and literal runs. Attackers can supply crafted LZF streams to applications using the default LZFDecoder to leak unrelated JVM heap memory into decompressed output or crash the JVM.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/github/securitylab/discussions/970 (technical-description)
- github.com/ning/compress (product)
- github.com/ning/compress/blob/compress-lzf-1.1.3/src/main/java/com/ning/compres… (technical-description)
- github.com/ning/compress/commit/06bdc3744a96b736a7118891f403e44c664f108b (patch)
- github.com/ning/compress/pull/68 (issue-tracking, patch)
- www.vulncheck.com/advisories/ning-compress-lzf-before-1.2.0-out-of-bounds-memor… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-109395?
- CVE-2026-109395 is a critical-severity vulnerability in Ning Compress-Lzf, classified under Out-of-bounds Read. CVSS score: 9.1/10. Published 2026-10-20.
- How severe is CVE-2026-109395?
- Critical severity. CVSS v3 base score is 9.1 out of 10.