CyberSecBulletin
CVE-2021-1905Exploited in the wildNVD status: Analyzed

Qualcomm Multiple Chipsets Use-After-Free

Published Updated By the CyberSecBulletin desk

CVE-2021-1905 is a high-severity use after free vulnerability in Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon Mobile, Snapdragon Voice & Music, Snapdragon Wearables from Qualcomm, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. CISA added it to the Known Exploited Vulnerabilities catalogue on November 3, 2021, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Check which version of Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon Mobile, Snapdragon Voice & Music, Snapdragon Wearables you run against the affected versions below, and install the vendor's latest release.
  2. CISA's required action: Apply updates per vendor instructions.
  3. Read the advisory on qualcomm.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
QualcommSnapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon Mobile, Snapdragon Voice & Music, Snapdragon WearablesNot specified in the recordNot stated
QualcommApq8009 FirmwareNot specified in the recordNot stated
QualcommApq8009w FirmwareNot specified in the recordNot stated
QualcommApq8017 FirmwareNot specified in the recordNot stated
QualcommApq8053 FirmwareNot specified in the recordNot stated
QualcommApq8064au FirmwareNot specified in the recordNot stated
QualcommApq8096au FirmwareNot specified in the recordNot stated
QualcommAqt1000 FirmwareNot specified in the recordNot stated
QualcommAr8031 FirmwareNot specified in the recordNot stated
QualcommAr8035 FirmwareNot specified in the recordNot stated
QualcommAr8151 FirmwareNot specified in the recordNot stated
QualcommCsra6620 FirmwareNot specified in the recordNot stated
QualcommCsra6640 FirmwareNot specified in the recordNot stated
QualcommFsm10055 FirmwareNot specified in the recordNot stated
QualcommFsm10056 FirmwareNot specified in the recordNot stated
QualcommMdm9206 FirmwareNot specified in the recordNot stated
QualcommMdm9607 FirmwareNot specified in the recordNot stated
QualcommMdm9626 FirmwareNot specified in the recordNot stated
QualcommMdm9628 FirmwareNot specified in the recordNot stated
QualcommMdm9650 FirmwareNot specified in the recordNot stated
QualcommMsm8909w FirmwareNot specified in the recordNot stated
QualcommMsm8917 FirmwareNot specified in the recordNot stated
QualcommMsm8953 FirmwareNot specified in the recordNot stated
QualcommMsm8996au FirmwareNot specified in the recordNot stated
QualcommPm215 FirmwareNot specified in the recordNot stated

Version data comes from the organisation that assigned the CVE; 35 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.4HighCNA (qualcomm.com)
CVSS 3.17.8HighNVD
CVSS 2.07.2HighNVD

Official description

Possible use after free due to improper handling of memory mapping of multiple processes simultaneously. in Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon Mobile, Snapdragon Voice & Music, Snapdragon Wearables

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon Mobile, Snapdragon Voice & Music, Snapdragon Wearables

All Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon Mobile, Snapdragon Voice & Music, Snapdragon Wearables vulnerabilities

Recent Use After Free vulnerabilities

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