DEBIAN-CVE-2026-89651

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Source

https://security-tracker.debian.org/tracker/CVE-2026-89651

Import Source

https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-89651.json

JSON Data

https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-89651

Upstream

CVE-2026-89651

Published

2026-09-11T20:19:51Z

Modified

2026-09-14T09:00:24Z

Severity

9.8 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator

Summary

[none]

Details

In the Linux kernel, the following vulnerability has been resolved: ceph: bound MDSCapAuth path and fs_name decode in handle_session() handle_session() decodes the MDSCapAuth records carried by a CEPH_SESSION_OPEN message (msg_version >= 6). For each record the match.path and match.fs_name byte strings are read by first decoding a 32-bit length and then copying that many bytes with the bare ceph_decode_copy(). Unlike the surrounding fields, which all use the _safe decode variants, these two copies are not preceded by a ceph_decode_need() bounds check, and the enclosing MDSCapAuth and MDSCapMatch struct_len fields are skipped rather than enforced as an upper bound. A length larger than the bytes remaining in the message front makes ceph_decode_copy() read past the end of the front buffer. The message front is a dedicated allocation (ceph_msg_new2() -> kvmalloc), so the over-read runs off that object. A malicious or compromised MDS can trigger this with the first post-connect message on mount, with no client-side user interaction; under KASAN it is reported as a slab-out-of-bounds read in handle_session(). Impact: a malicious MDS can force the kernel client to read up to 4 GiB past the message front allocation during session setup, crashing the client (out-of-bounds read). Switch both copies to ceph_decode_copy_safe(), which performs the ceph_decode_need() bounds check before the copy and branches to the existing bad label, matching the rest of the decoder and the error path that frees the partially decoded cap_auths array.

References

https://security-tracker.debian.org/tracker/CVE-2026-89651

Affected packages

Debian:13 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source&distro=trixie

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0 Unknown introduced version / All previous versions are affected

Affected versions

6.*

6.12.38-1

6.12.41-1

6.12.43-1~bpo12+1

6.12.43-1

6.12.48-1

6.12.57-1~bpo12+1

6.12.57-1

6.12.63-1~bpo12+1

6.12.63-1

6.12.69-1~bpo12+1

6.12.69-1

6.12.73-1~bpo12+1

6.12.73-1

6.12.74-1

6.12.74-2~bpo12+1

6.12.74-2

6.12.85-1~bpo12+1

6.12.85-1

6.12.86-1~bpo12+1

6.12.86-1

6.12.88-1~bpo12+1

6.12.88-1

6.12.90-1~bpo12+1

6.12.90-1

6.12.90-2~bpo12+1

6.12.90-2

6.12.94-1~bpo12+1

6.12.94-1

6.12.95-1~bpo12+1

6.12.95-1

6.12.96-1

6.12.100-1

6.12.101-1

6.12.105-1

6.12.107-1

6.13~rc6-1~exp1

6.13~rc7-1~exp1

6.13.2-1~exp1

6.13.3-1~exp1

6.13.4-1~exp1

6.13.5-1~exp1

6.13.6-1~exp1

6.13.7-1~exp1

6.13.8-1~exp1

6.13.9-1~exp1

6.13.10-1~exp1

6.13.11-1~exp1

6.14.3-1~exp1

6.14.5-1~exp1

6.14.6-1~exp1

6.15~rc7-1~exp1

6.15-1~exp1

6.15.1-1~exp1

6.15.2-1~exp1

6.15.3-1~exp1

6.15.4-1~exp1

6.15.5-1~exp1

6.15.6-1~exp1

6.16~rc7-1~exp1

6.16-1~exp1

6.16.1-1~exp1

6.16.3-1~bpo13+1

6.16.3-1

6.16.5-1

6.16.6-1

6.16.7-1

6.16.8-1

6.16.9-1

6.16.10-1

6.16.11-1

6.16.12-1~bpo13+1

6.16.12-1

6.16.12-2

6.17.2-1~exp1

6.17.5-1~exp1

6.17.6-1

6.17.7-1

6.17.7-2

6.17.8-1~bpo13+1

6.17.8-1

6.17.9-1

6.17.10-1

6.17.11-1

6.17.12-1

6.17.13-1~bpo13+1

6.17.13-1

6.18~rc4-1~exp1

6.18~rc4-1~exp2

6.18~rc5-1~exp1

6.18~rc6-1~exp1

6.18~rc7-1~exp1

6.18.1-1~exp1

6.18.2-1~exp1

6.18.3-1

6.18.5-1~bpo13+1

6.18.5-1

6.18.8-1

6.18.9-1~bpo13+1

6.18.9-1

6.18.10-1

6.18.12-1~bpo13+1

6.18.12-1

6.18.13-1

6.18.14-1

6.18.15-1~bpo13+1

6.18.15-1

6.19~rc4-1~exp1

6.19~rc5-1~exp1

6.19~rc6-1~exp1

6.19~rc7-1~exp1

6.19~rc8-1~exp1

6.19-1~exp1

6.19.2-1~exp1

6.19.3-1~exp1

6.19.4-1~exp1

6.19.5-1~exp1

6.19.6-1

6.19.6-2~bpo13+1

6.19.6-2

6.19.8-1~bpo13+1

6.19.8-1

6.19.10-1~bpo13+1

6.19.10-1

6.19.11-1~bpo13+1

6.19.11-1

6.19.12-1

6.19.13-1~bpo13+1

6.19.13-1

6.19.14-1~bpo13+1

6.19.14-1

7.*

7.0-1~exp1

7.0.1-1~exp1

7.0.3-1

7.0.4-1~bpo13+1

7.0.4-1

7.0.7-1~bpo13+1

7.0.7-1

7.0.9-1~bpo13+1

7.0.9-1

7.0.10-1~bpo13+1

7.0.10-1

7.0.12-1

7.0.12-2~bpo13+1

7.0.12-2

7.0.13-1~bpo13+1

7.0.13-1

7.0.14-1

7.1~rc2-1~exp1

7.1~rc3-1~exp1

7.1~rc4-1~exp1

7.1~rc4-1~exp2

7.1~rc5-1~exp1

7.1~rc7-1~exp1

7.1.1-1~exp1

7.1.2-1~exp1

7.1.3-1~bpo13+1

7.1.3-1

7.1.3-1+sunvdc

7.1.4-1

7.1.5-1

7.1.6-1

7.1.7-1~bpo13+1

7.1.7-1

7.1.8-1~bpo13+1

7.1.8-1

7.1.8-2

7.1.9-1

7.1.9-1+sparc64

7.1.10-1

7.1.12-1

7.1.13-1

7.2~rc3-1~exp1

7.2~rc5-1~exp1

7.2~rc7-1~exp1

7.2.2-1~exp1

7.2.3-1~exp1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Database specific

source

"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-89651.json"

Debian:14 / linux