CVE-2026-31596 | Linux Kernel up to 6.12.82/6.18.23/6.19.13/7.0.0 Fileystems fs/ocfs2/resize.c ocfs2_group_extend buffer overflow

VDB-359397 · CVE-2026-31596 · GCVE-0-2026-31596 LINUX KERNEL UP TO 6.12.82/6.18.23/6.19.13/7.0.0 FILEYSTEMS FS/OCFS2/RESIZE.C OCFS2_GROUP_EXTEND BUFFER OVERFLOW HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 7.6 $5k-$25k 0.57+ Summaryinfo A vulnerability has been found in Linux Kernel up to 6.12.82/6.18.23/6.19.13/7.0.0 and classified as critical. Impacted is the function ocfs2_group_extend of the file fs/ocfs2/resize.c of the component Fileystems Handler. Performing a manipulation results in buffer overflow. This vulnerability is reported as CVE-2026-31596. No exploit exists. The affected component should be upgraded. Detailsinfo A vulnerability classified as critical has been found in Linux Kernel up to 6.12.82/6.18.23/6.19.13/7.0.0. This affects the function ocfs2_group_extend of the file fs/ocfs2/resize.c of the component Fileystems Handler. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is: In the Linux kernel, the following vulnerability has been resolved: ocfs2: handle invalid dinode in ocfs2_group_extend [BUG] kernel BUG at fs/ocfs2/resize.c:308! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI RIP: 0010:ocfs2_group_extend+0x10aa/0x1ae0 fs/ocfs2/resize.c:308 Code: 8b8520ff ffff83f8 860f8580 030000e8 5cc3c1fe Call Trace: ... ocfs2_ioctl+0x175/0x6e0 fs/ocfs2/ioctl.c:869 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x197/0x1e0 fs/ioctl.c:583 x64_sys_call+0x1144/0x26a0 arch/x86/include/generated/asm/syscalls_64.h:17 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x93/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e ... [CAUSE] ocfs2_group_extend() assumes that the global bitmap inode block returned from ocfs2_inode_lock() has already been validated and BUG_ONs when the signature is not a dinode. That assumption is too strong for crafted filesystems because the JBD2-managed buffer path can bypass structural validation and return an invalid dinode to the resize ioctl. [FIX] Validate the dinode explicitly in ocfs2_group_extend(). If the global bitmap buffer does not contain a valid dinode, report filesystem corruption with ocfs2_error() and fail the resize operation instead of crashing the kernel. The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-31596 since 03/09/2026. The exploitability is told to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 04/24/2026). Upgrading to version 6.12.83, 6.18.24, 6.19.14 or 7.0.1 eliminates this vulnerability. Applying the patch 911b557dd7817460881fd51a03069b539c674d0e/e384a850a3370d89a7a446cdeccd964bfba2a302/10fb72c47aac446f12a4ccd962c7daa60cc890a1/41c6e9bc3a09539deab43957a3211d902a4818f0 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version. Productinfo Type Operating System Vendor Linux Name Kernel Version 6.12.0 6.12.1 6.12.2 6.12.3 6.12.4 6.12.5 6.12.6 6.12.7 6.12.8 6.12.9 6.12.10 6.12.11 6.12.12 6.12.13 6.12.14 6.12.15 6.12.16 6.12.17 6.12.18 6.12.19 6.12.20 6.12.21 6.12.22 6.12.23 6.12.24 6.12.25 6.12.26 6.12.27 6.12.28 6.12.29 6.12.30 6.12.31 6.12.32 6.12.33 6.12.34 6.12.35 6.12.36 6.12.37 6.12.38 6.12.39 6.12.40 6.12.41 6.12.42 6.12.43 6.12.44 6.12.45 6.12.46 6.12.47 6.12.48 6.12.49 6.12.50 6.12.51 6.12.52 6.12.53 6.12.54 6.12.55 6.12.56 6.12.57 6.12.58 6.12.59 6.12.60 6.12.61 6.12.62 6.12.63 6.12.64 6.12.65 6.12.66 6.12.67 6.12.68 6.12.69 6.12.70 6.12.71 6.12.72 6.12.73 6.12.74 6.12.75 6.12.76 6.12.77 6.12.78 6.12.79 6.12.80 6.12.81 6.12.82 6.18.0 6.18.1 6.18.2 6.18.3 6.18.4 6.18.5 6.18.6 6.18.7 6.18.8 6.18.9 6.18.10 6.18.11 6.18.12 6.18.13 6.18.14 6.18.15 6.18.16 6.18.17 6.18.18 6.18.19 6.18.20 6.18.21 6.18.22 6.18.23 6.19.0 6.19.1 6.19.2 6.19.3 6.19.4 6.19.5 6.19.6 6.19.7 6.19.8 6.19.9 6.19.10 6.19.11 6.19.12 6.19.13 7.0 License open-source Website Vendor: https://www.kernel.org/ CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 8.0 VulDB Meta Temp Score: 7.6 VulDB Base Score: 8.0 VulDB Temp Score: 7.6 VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Buffer overflow CWE: CWE-120 / CWE-119 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Partially Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: Kernel 6.12.83/6.18.24/6.19.14/7.0.1 Patch: 911b557dd7817460881fd51a03069b539c674d0e/e384a850a3370d89a7a446cdeccd964bfba2a302/10fb72c47aac446f12a4ccd962c7daa60cc890a1/41c6e9bc3a09539deab43957a3211d902a4818f0 Timelineinfo 03/09/2026 CVE reserved 04/24/2026 +45 days Advisory disclosed 04/24/2026 +0 days VulDB entry created 04/24/2026 +0 days VulDB entry last update Sourcesinfo Vendor: kernel.org Advisory: git.kernel.org Status: Confirmed CVE: CVE-2026-31596 (🔒) GCVE (CVE): GCVE-0-2026-31596 GCVE (VulDB): GCVE-100-359397 Entryinfo Created: 04/24/2026 17:53 Changes: 04/24/2026 17:53 (60) Complete: 🔍 Cache ID: 99:20F:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸