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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2025-38433— riscv: fix runtime constant support for nommu kernels

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.

Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于riscv架构中nommu内核的运行时常量支持处理不当，可能导致内核崩溃。

AI Predicted 5.5 Difficulty: Hard EPSS 0.15% · P4

Possible ATT&CK Techniques 1 AI

T1068 · Exploitation for Privilege Escalation

Affected Version Matrix 6

VendorProduct Version RangeStatus
Linux Linux a44fb5722199de8338d991db5ad3d509192179bb< 0a24b00dcde83934a3cc13e4c6b775522903496b affected
a44fb5722199de8338d991db5ad3d509192179bb< 8d90d9872edae7e78c3a12b98e239bfaa66f3639 affected
6.15 affected
< 6.15 unaffected
6.15.5≤ 6.15.* unaffected
6.16≤ * unaffected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2025-38433

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
riscv: fix runtime constant support for nommu kernels
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: riscv: fix runtime constant support for nommu kernels the `__runtime_fixup_32` function does not handle the case where `val` is zero correctly (as might occur when patching a nommu kernel and referring to a physical address below the 4GiB boundary whose upper 32 bits are all zero) because nothing in the existing logic prevents the code from taking the `else` branch of both nop-checks and emitting two `nop` instructions. This leaves random garbage in the register that is supposed to receive the upper 32 bits of the pointer instead of zero that when combined with the value for the lower 32 bits yields an invalid pointer and causes a kernel panic when that pointer is eventually accessed. The author clearly considered the fact that if the `lui` is converted into a `nop` that the second instruction needs to be adjusted to become an `li` instead of an `addi`, hence introducing the `addi_insn_mask` variable, but didn't follow that logic through fully to the case where the `else` branch executes. To fix it just adjust the logic to ensure that the second `else` branch is not taken if the first instruction will be patched to a `nop`.
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
Vulnerability Title
Linux kernel 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Linux kernel是美国Linux基金会的开源操作系统Linux所使用的内核。 Linux kernel存在安全漏洞，该漏洞源于riscv架构中nommu内核的运行时常量支持处理不当，可能导致内核崩溃。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
Linux Linux a44fb5722199de8338d991db5ad3d509192179bb ~ 0a24b00dcde83934a3cc13e4c6b775522903496b -
Linux Linux 6.15 -

II. Public POCs for CVE-2025-38433

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2025-38433

请登录查看更多情报信息。

Same Patch Batch · Linux · 2025-07-25 · 114 CVEs total

CVE-2025-38429 10.0 CRITICAL bus: mhi: ep: Update read pointer only after buffer is written
CVE-2025-38411 9.8 CRITICAL netfs: Fix double put of request
CVE-2025-38430 9.8 CRITICAL nfsd: nfsd4_spo_must_allow() must check this is a v4 compound request
CVE-2025-38439 9.8 CRITICAL bnxt_en: Set DMA unmap len correctly for XDP_REDIRECT
CVE-2025-38365 9.1 CRITICAL btrfs: fix a race between renames and directory logging
CVE-2025-38377 8.8 HIGH rose: fix dangling neighbour pointers in rose_rt_device_down()
CVE-2025-38367 8.8 HIGH LoongArch: KVM: Avoid overflow with array index
CVE-2025-38437 8.8 HIGH ksmbd: fix potential use-after-free in oplock/lease break ack
CVE-2025-38375 8.4 HIGH virtio-net: ensure the received length does not exceed allocated size
CVE-2025-38395 8.4 HIGH regulator: gpio: Fix the out-of-bounds access to drvdata::gpiods
CVE-2025-38386 7.8 HIGH ACPICA: Refuse to evaluate a method if arguments are missing
CVE-2025-38422 7.8 HIGH net: lan743x: Modify the EEPROM and OTP size for PCI1xxxx devices
CVE-2025-38434 7.8 HIGH Revert "riscv: Define TASK_SIZE_MAX for __access_ok()"
CVE-2025-38449 7.8 HIGH drm/gem: Acquire references on GEM handles for framebuffers
CVE-2025-38382 7.8 HIGH btrfs: fix iteration of extrefs during log replay
CVE-2025-38412 7.8 HIGH platform/x86: dell-wmi-sysman: Fix WMI data block retrieval in sysfs callbacks
CVE-2025-38447 7.8 HIGH mm/rmap: fix potential out-of-bounds page table access during batched unmap
CVE-2025-38398 7.8 HIGH spi: spi-qpic-snand: reallocate BAM transactions
CVE-2025-38408 7.8 HIGH genirq/irq_sim: Initialize work context pointers properly
CVE-2025-38396 7.8 HIGH fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass

Showing top 20 of 114 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2025-38433

No comments yet

Leave a comment