Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%
Buy Us a Coffee

CVE-2026-89718— zram: fix out-of-bounds access in writeback_store()

Quick assessment

Affected
Linux Linux
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

以下是该 Linux 内核漏洞描述信息的中文翻译： Linux 内核中修复了一个漏洞： zram：修复 writeback_store() 中的越界访问 补丁系列：“zram：修复重新初始化后过时的扫描边界” 和 均在获取 之前，基于 计算表格扫描边界。如果在该读取与获取锁之间，设备被重置并以更小的 重新初始化，那么边界值可能仍对应旧表格，而扫描操作却作用于新表格。这可能导致对槽位的越界访问。 将两处边界计算移至 保护范围内，以确保每个边界值在整个扫描过程中与所保护的表格保持一致。由于受影响的接口源自不同的提交，因

AI Predicted 5.5 Difficulty: Hard

Possible ATT&CK Techniques 1 AI

T1300

Affected Version Matrix 6

VendorProduct Version RangeStatus
Linux Linux a939888ec38bf1f33e4a903056677e92a4844244< 07a82a66f8c1894d92e51d97542c32ebf2c51b09 affected
a939888ec38bf1f33e4a903056677e92a4844244< 894913e2d35c46ff19a77530907771ae57862b96 affected
5.0 affected
< 5.0 unaffected
7.2.4≤ 7.2.* unaffected
7.3-rc1≤ * unaffected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-89718

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
zram: fix out-of-bounds access in writeback_store()
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: zram: fix out-of-bounds access in writeback_store() Patch series "zram: fix stale scan bounds after reinitialization". Both writeback_store() and read_block_state() derive their table scan bounds from zram->disksize before acquiring dev_lock. If the device is reset and reinitialized with a smaller disksize between that read and lock acquisition, the bound can describe the old table while the scan operates on the new one. This can lead to out-of-bounds slot accesses. Move both bound calculations under dev_lock so each bound remains consistent with the table throughout its scan. Keep the fixes separate because the affected interfaces originate from different commits and can be backported independently. This patch (of 2): writeback_store() calculates the table scan bounds before taking dev_lock. A reset followed by reconfiguration with a smaller disksize can therefore replace zram->table while writeback_store() is waiting for the lock. Once it acquires the lock, it sees an initialized device but scans the new table using the old upper bound, resulting in an out-of-bounds access. Calculate the number of pages while holding dev_lock so the scan bound matches the table protected by the lock.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
N/A
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux a939888ec38bf1f33e4a903056677e92a4844244 ~ 07a82a66f8c1894d92e51d97542c32ebf2c51b09 -
Linux Linux 5.0 -

II. Public POCs for CVE-2026-89718

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-89718

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-89718 (2)

Same Patch Batch · Linux · 2026-09-11 · 431 CVEs total

CVE-2026-89491 ocfs2: cluster: don't sleep while holding o2hb_live_lock in o2hb_region_pin()
CVE-2026-89477 sctp: fix NULL deref on untransmitted RECONF completion
CVE-2026-89478 sctp: drop a chunk if its transport was removed
CVE-2026-89479 sctp: stop processing a packet once its association is deleted
CVE-2026-89480 nvme-tcp: reject a read that transferred too few bytes
CVE-2026-89482 nvme-tcp: do not accept C2HData based on blk_rq_payload_bytes() alone
CVE-2026-89481 nvme-tcp: fix host memory disclosure on R2T for a read command
CVE-2026-89483 nvme: zero the discard fallback page
CVE-2026-89484 lockd: fix NULL dereference on lockowner allocation failure
CVE-2026-89485 lockd: pin next file across nlm_inspect_file lock-drop
CVE-2026-89486 ipmi: Fix use-after-free of cmd_rcvr in _ipmi_destroy_user()
CVE-2026-89487 openvswitch: only skb_tx_error() a packet we are about to drop
CVE-2026-89488 openvswitch: Fix CT limit teardown use-after-free
CVE-2026-89489 openrisc: fix arbitrary kernel memory access via or1k_atomic syscall
CVE-2026-89500 ring-buffer: Make cpu_buffer::free_page a buffer_data_read_page
CVE-2026-89497 orangefs: skip leading spaces before parsing client debug masks
CVE-2026-89498 orangefs: fix double-free of trailer_buf on readdir copy failure
CVE-2026-89499 ring-buffer: Stop remote reader update when page swap fails
CVE-2026-89496 ocfs2: always run deallocs on copy-on-write completion
CVE-2026-89501 ring-buffer: Hold cpu_buffer::lock when resizing a subbuf

Showing top 20 of 431 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2026-89718

No comments yet

Leave a comment