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

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2021-47200— drm/prime: Fix use after free in mmap with drm_gem_ttm_mmap

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drm_gem_ttm_mmap存在释放后重用漏洞。

CVSS 7.8 · High EPSS 0.22% · P12

Possible ATT&CK Techniques 1 AI

T1203 · Exploitation for Client Execution

Affected Version Matrix 6

VendorProduct Version RangeStatus
Linux Linux 9786b65bc61acec63f923978c75e707afbb74bc7< 4f8e469a2384dfa4047145b0093126462cbb6dc0 affected
9786b65bc61acec63f923978c75e707afbb74bc7< 8244a3bc27b3efd057da154b8d7e414670d5044f affected
5.5 affected
< 5.5 unaffected
5.15.5≤ 5.15.* unaffected
5.16≤ * unaffected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2021-47200

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Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.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
drm/prime: Fix use after free in mmap with drm_gem_ttm_mmap
Source: CVE Program / CVE List V5
Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: drm/prime: Fix use after free in mmap with drm_gem_ttm_mmap drm_gem_ttm_mmap() drops a reference to the gem object on success. If the gem object's refcount == 1 on entry to drm_gem_prime_mmap(), that drop will free the gem object, and the subsequent drm_gem_object_get() will be a UAF. Fix by grabbing a reference before calling the mmap helper. This issue was forseen when the reference dropping was adding in commit 9786b65bc61ac ("drm/ttm: fix mmap refcounting"): "For that to work properly the drm_gem_object_get() call in drm_gem_ttm_mmap() must be moved so it happens before calling obj->funcs->mmap(), otherwise the gem refcount would go down to zero."
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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drm_gem_ttm_mmap存在释放后重用漏洞。
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 9786b65bc61acec63f923978c75e707afbb74bc7 ~ 4f8e469a2384dfa4047145b0093126462cbb6dc0 -
Linux Linux 5.5 -

II. Public POCs for CVE-2021-47200

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

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2021-47200

请登录查看更多情报信息。

Other References for CVE-2021-47200 (2)

Same Patch Batch · Linux · 2024-04-10 · 39 CVEs total

CVE-2021-47215 9.8 CRITICAL net/mlx5e: kTLS, Fix crash in RX resync flow
CVE-2021-47203 8.8 HIGH scsi: lpfc: Fix list_add() corruption in lpfc_drain_txq()
CVE-2021-47183 8.8 HIGH scsi: lpfc: Fix link down processing to address NULL pointer dereference
CVE-2021-47184 8.8 HIGH i40e: Fix NULL ptr dereference on VSI filter sync
CVE-2021-47201 7.8 HIGH iavf: free q_vectors before queues in iavf_disable_vf
CVE-2024-26815 7.8 HIGH net/sched: taprio: proper TCA_TAPRIO_TC_ENTRY_INDEX check
CVE-2021-47197 7.8 HIGH net/mlx5e: nullify cq->dbg pointer in mlx5_debug_cq_remove()
CVE-2021-47196 7.8 HIGH RDMA/core: Set send and receive CQ before forwarding to the driver
CVE-2021-47188 7.8 HIGH scsi: ufs: core: Improve SCSI abort handling
CVE-2021-47189 7.8 HIGH btrfs: fix memory ordering between normal and ordered work functions
CVE-2021-47209 7.8 HIGH sched/fair: Prevent dead task groups from regaining cfs_rq's
CVE-2021-47194 7.8 HIGH cfg80211: call cfg80211_stop_ap when switch from P2P_GO type
CVE-2021-47219 7.1 HIGH scsi: scsi_debug: Fix out-of-bound read in resp_report_tgtpgs()
CVE-2021-47191 7.1 HIGH scsi: scsi_debug: Fix out-of-bound read in resp_readcap16()
CVE-2021-47211 ALSA: usb-audio: fix null pointer dereference on pointer cs_desc
CVE-2021-47210 usb: typec: tipd: Remove WARN_ON in tps6598x_block_read
CVE-2021-47212 net/mlx5: Update error handler for UCTX and UMEM
CVE-2021-47214 hugetlb, userfaultfd: fix reservation restore on userfaultfd error
CVE-2021-47216 scsi: advansys: Fix kernel pointer leak
CVE-2021-47217 x86/hyperv: Fix NULL deref in set_hv_tscchange_cb() if Hyper-V setup fails

Showing top 20 of 39 CVEs. View all on vendor page &rarr; →

IV. Related Vulnerabilities

Same product: Linux
Same vendor: Linux

V. Comments for CVE-2021-47200

No comments yet

Leave a comment