CVE-2021-47475
In the Linux kernel, the following vulnerability has been resolved: comedi: vmk80xx: fix transfer-buffer overflows The driver uses endpoint-sized USB transfer buffers but up until recently had no sanity checks on the sizes.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.26%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: comedi: vmk80xx: fix transfer-buffer overflows The driver uses endpoint-sized USB transfer buffers but up until recently had no sanity checks on the sizes. Commit e1f13c879a7c ("staging: comedi: check validity of wMaxPacketSize of usb endpoints found") inadvertently fixed NULL-pointer dereferences when accessing the transfer buffers in case a malicious device has a zero wMaxPacketSize. Make sure to allocate buffers large enough to handle also the other accesses that are done without a size check (e.g. byte 18 in vmk80xx_cnt_insn_read() for the VMK8061_MODEL) to avoid writing beyond the buffers, for example, when doing descriptor fuzzing. The original driver was for a low-speed device with 8-byte buffers. Support was later added for a device that uses bulk transfers and is presumably a full-speed device with a maximum 64-byte wMaxPacketSize.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.26% probability · 18th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/06ac746d57e6d32b062e220415c607b7e2e0fa50Patch
- https://git.kernel.org/stable/c/199acd8c110e3ae62833c24f632b0bb1c9f012a9Patch
- https://git.kernel.org/stable/c/278484ae93297b1bb1ce755f9d3b6d95a48c7d47Patch
- https://git.kernel.org/stable/c/33d7a470730dfe7c9bfc8da84575cf2cedd60d00Patch
- https://git.kernel.org/stable/c/40d2a7e278e2e7c0a5fd7e997e7eb63945bf93f7Patch
- https://git.kernel.org/stable/c/5229159f1d052821007aff1a1beb7873eacf1a9fPatch
- https://git.kernel.org/stable/c/7a2021b896de1ad559d33b5c5cdd20b982242088Patch
- https://git.kernel.org/stable/c/a23461c47482fc232ffc9b819539d1f837adf2b1Patch
- https://git.kernel.org/stable/c/ec85bcff4ed09260243d8f39faba99e1041718baPatch
- https://git.kernel.org/stable/c/06ac746d57e6d32b062e220415c607b7e2e0fa50Patch
- https://git.kernel.org/stable/c/199acd8c110e3ae62833c24f632b0bb1c9f012a9Patch
- https://git.kernel.org/stable/c/278484ae93297b1bb1ce755f9d3b6d95a48c7d47Patch
- https://git.kernel.org/stable/c/33d7a470730dfe7c9bfc8da84575cf2cedd60d00Patch
- https://git.kernel.org/stable/c/40d2a7e278e2e7c0a5fd7e997e7eb63945bf93f7Patch
- https://git.kernel.org/stable/c/5229159f1d052821007aff1a1beb7873eacf1a9fPatch
- https://git.kernel.org/stable/c/7a2021b896de1ad559d33b5c5cdd20b982242088Patch
- https://git.kernel.org/stable/c/a23461c47482fc232ffc9b819539d1f837adf2b1Patch
- https://git.kernel.org/stable/c/ec85bcff4ed09260243d8f39faba99e1041718baPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.