CVE-2025-67721: Aircompressor is a library with ports of the Snappy, LZO, LZ4, and Zstandard compression algorithms to Java

This month

HIGH 7.5REMOTEUPGRADE

CVE-2025-67721 is a high-severity flaw (CVSS 7.5) affecting aircompressor. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Aircompressor is a library with ports of the Snappy, LZO, LZ4, and Zstandard compression algorithms to Java. In versions 3.3 and below, incorrect handling of malformed data in Java-based decompressor implementations for Snappy and LZ4 allow remote attackers to read previous buffer contents via crafted compressed input. With certain crafted compressed inputs, elements from the output buffer can end up in the uncompressed output, potentially leakin

Why this priority

High severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.5% (top 56%)
CISA exploited list	No
Weakness	CWE-125, CWE-201
Published	2025-12-12
Last modified	2026-10-07

Publisher (CNA): GitHub, Inc. · Vendor: airlift

Last updated 2026-10-07 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2025-12-12 23:15 UTCPublished CVE record published
2026-10-07 20:10 UTCUpdated Record last modified

airlift aircompressor UPGRADE

Affected: < 2.0.3 · >= 3.0 and < 3.4

Fixed in: 2.0.3, 3.4

Safe to downgrade to: a release before 3.0

1. Check installed version

apt-cache policy aircompressor || rpm -q aircompressor || aircompressor --version

2. UPGRADE to 2.0.3 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade aircompressor

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade aircompressor

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 3.0 (Debian / Ubuntu)

apt-cache madison aircompressor sudo apt install aircompressor=<VERSION_BEFORE_3.0> sudo apt-mark hold aircompressor

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list aircompressor sudo dnf downgrade aircompressor-<VERSION_BEFORE_3.0> sudo dnf versionlock add aircompressor

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2025-67721?

aircompressor: upgrade to 2.0.3, 3.4. Exact commands for each OS are on this page.

Is CVE-2025-67721 being exploited?

CVE-2025-67721 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2025-67721 affect?

CVE-2025-67721 affects aircompressor. Severity is high (CVSS 7.5). Aircompressor is a library with ports of the Snappy, LZO, LZ4, and Zstandard compression algorithms to Java. In versions 3.3 and below, incorrect handling of malformed data in Java-based decompressor implementations for Snappy and LZ4 allow

How urgent is CVE-2025-67721?

Priority 42/100. High severity; Remotely exploitable, no login, no user action

Software pages

Java vulnerabilities

References

← Back to latest CVEs