CVE-2026-116188: rclone serve s3 versions 1.75.0 before 1.75.2 contain an integer overflow vulnerability in multipart reorder-m

Routine

MEDIUM 5.3REMOTEUPGRADE

CVE-2026-116188 is a medium-severity flaw (CVSS 5.3) affecting rclone. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

rclone serve s3 versions 1.75.0 before 1.75.2 contain an integer overflow vulnerability in multipart reorder-memory accounting that bypasses the configured buffer limit. Attackers can open two concurrent current-part PUT requests declaring huge lengths to wrap the signed int64 counter and retain out-of-order parts in memory, exhausting the host.

Why this priority

Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	5.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.3% (top 81%)
CISA exploited list	No
Weakness	CWE-190
Published	2026-10-25
Last modified	2026-10-28

Publisher (CNA): VulnCheck · Vendor: rclone

Last updated 2026-10-28 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-10-25 14:16 UTCPublished CVE record published
2026-10-28 15:39 UTCUpdated Record last modified

rclone rclone UPGRADE

Affected: >= 1.75.0 and < 1.75.2

Fixed in: 1.75.2

Safe to downgrade to: a release before 1.75.0

1. Check installed version

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

2. UPGRADE to 1.75.2 (Debian / Ubuntu)

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

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade rclone

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 1.75.0 (Debian / Ubuntu)

apt-cache madison rclone sudo apt install rclone=<VERSION_BEFORE_1.75.0> sudo apt-mark hold rclone

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

dnf --showduplicates list rclone sudo dnf downgrade rclone-<VERSION_BEFORE_1.75.0> sudo dnf versionlock add rclone

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-2026-116188?

rclone: upgrade to 1.75.2. Exact commands for each OS are on this page.

Is CVE-2026-116188 being exploited?

CVE-2026-116188 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-2026-116188 affect?

CVE-2026-116188 affects rclone. Severity is medium (CVSS 5.3). rclone serve s3 versions 1.75.0 before 1.75.2 contain an integer overflow vulnerability in multipart reorder-memory accounting that bypasses the configured buffer limit. Attackers can open two concurrent current-part PUT requests declaring

How urgent is CVE-2026-116188?

Priority 28/100. Remotely exploitable, no login, no user action

Related CVEs

CVE-2026-116187 MEDIUM 5.0 UPGRADE Rclone from v1.68.0 before v1.75.2 contains an authorization bypass vulnerability in serve s3 --auth-proxy tha
CVE-2026-116189 HIGH 7.5 UPGRADE rclone from 1.55.0 before 1.75.2 contains a signature verification bypass in stable selfupdate that trusts che
CVE-2026-116190 LOW 3.7 UPGRADE rclone from v1.56.0 before v1.75.2 contains an information disclosure vulnerability in the WebDAV backend that
CVE-2026-116196 MEDIUM 5.3 UPGRADE Rclone before v1.75.2 contains a credential exposure vulnerability in the b2 backend that leaks the live accou
CVE-2026-116195 MEDIUM 6.1 UPGRADE Rclone before 1.75.2 contains a path traversal vulnerability in the local backend's translateLink function, wh

References

← Back to latest CVEs