CVE-2026-88045
rclone: S3 multipart declared-length memory exhaustion
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
rclone is a command-line program to sync files and directories to and from different cloud storage providers. From 1.75.0 until 1.75.1, the serve S3 streamed multipart path in cmd/serve/s3/multipart.go passes attacker-controlled contentLength to multipart.NewRW().Reserve before reading request-body bytes. waitForTurn admits the current part and one oversized part when the buffer is empty despite --multipart-streaming-buffer-limit, and lib/pool allocates 1 MiB pages according to Content-Length or X-Amz-Decoded-Content-Length. A network client can retain or multiply these reservations without sending the declared body, exhausting process or host memory or permanently blocking request handlers. Anonymous S3 deployments require no credentials, while deployments using auth_key require an accepted S3 key. This issue is fixed in version 1.75.1.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
- https://github.com/rclone/rclone/security/advisories/GHSA-2p48-j3qc-rx9f (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 1 day later
· 1 day later
Published
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Awaiting Analysis | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.63% · top 50% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
Affected products
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/rclone/rcloneGHSA-2p48-j3qc-rx9f (opens in a new tab)
References (5)
- https://github.com/rclone/rclone/security/advisories/GHSA-2p48-j3qc-rx9f (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/rclone/rclone/issues/9616 (opens in a new tab)x_refsource_MISC
- https://github.com/rclone/rclone/commit/7c1dfd99f3e6a22fcefd8686cc478226a15e63a1 (opens in a new tab)x_refsource_MISC
- https://github.com/rclone/rclone/commit/ab1f458013aaf6356e4bdeca61f7cb9139f8eb86 (opens in a new tab)x_refsource_MISC
- https://github.com/rclone/rclone/releases/tag/v1.75.1 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-2p48-j3qc-rx9f (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-88045)Record last updated .