[ CVE-2026-98127 · Published 25 Sep 2026 ]
Vulnerability in Linux
[ Description ]Official description
In the Linux kernel, the following vulnerability has been resolved: smb/client: validate new EOF for insert range smb3_insert_range() does not check if the new file size (i_size + len) is valid. This allows FALLOC_FL_INSERT_RANGE to bypass RLIMIT_FSIZE, exceed s_maxbytes, or produce a size outside the loff_t range. Use check_add_overflow() to calculate the new EOF. Validate it with inode_newsize_ok() before modifying the file. Reproducer, using a file on a CIFS mount: bash -c ' FILE=/mnt/cifs/repro trap "" SIGXFSZ ulimit -f 3072 # RLIMIT_FSIZE = 3 MiB # A regular write is stopped at 3 MiB. dd if=/dev/zero of="$FILE" bs=1M count=4 status=none stat -c "size after write: %s" "$FILE" # Insert 2 MiB into a 2 MiB file. truncate -s 2M "$FILE" fallocate -i -o 0 -l 2M "$FILE" stat -c "size after insert: %s" "$FILE" ' Before this change, the regular write stops at the 3 MiB limit, but insert range grows the file to 4 MiB: dd: error writing '/mnt/cifs/repro': File too large size after write: 3145728 size after insert: 4194304 After this change, insert range also fails at the limit and leaves the 2 MiB file unchanged: dd: error writing '/mnt/cifs/repro': File too large size after write: 3145728 fallocate: fallocate failed: File too large size after insert: 2097152
[ Fixes ]Fixes and patches
- Patch on git.kernel.orgVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
- Patch on git.kernel.orgVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
- Patch on git.kernel.orgVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
- Patch on git.kernel.orgVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
- Patch on git.kernel.orgVendor patch or bulletin · NVD · Reference tagged 'Patch' by NVD
[ Advisories ]Government CERT advisories
-
CERT-FRCERTFR-2026-AVI-1289
Multiple vulnerabilities in the Debian LTS Linux kernel Translated from French
Multiple vulnerabilities have been discovered in the Debian LTS Linux kernel. Some of them allow an attacker to cause privilege escalation, a breach of data confidentiality and denial of service.
-
CERT-FRCERTFR-2026-AVI-1253
Multiple vulnerabilities in the Debian Linux kernel Translated from French
Multiple vulnerabilities have been discovered in the Debian Linux kernel. Some of them allow an attacker to cause privilege escalation, a breach of data confidentiality and denial of service.
-
BSI CERT-BundWID-SEC-2026-3579
Linux Kernel: Multiple vulnerabilities Translated from German
[ References ]References
- git.kernel.org/stable/c/1519dc88c87f5346dae0464d7d6da1b6bf1f6e8ePatch
- git.kernel.org/stable/c/7c2c69045aa76ccaa7f16f1478eb312130ce4951Patch
- git.kernel.org/stable/c/b7f2e33d9f5db7b8e6e5e0a5a93d0c5e31870356Patch
- git.kernel.org/stable/c/bc7602b9082ef195d913c4c16fa9853dd262333ePatch
- git.kernel.org/stable/c/f8cbfe3a3fcee7d991fd223f660f3e5df13221cfPatch