Cyber Resilience

CVE-2021-1905

Memory Safety in Qualcomm Sd675 Firmware

CISA KEVActive ExploitationEUVD ExploitedMemory Safety
Published
07 May 2021
Modified
28 October 2025
KEV Added
03 November 2021
Patch / advisory
View advisory
CVSS Score v3.1 8.4
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.011 64th percentile
Risk Priority 88 floored blend · peak EPSS

Summary

CVE-2021-1905 is a high-severity Use After Free (CWE-416) vulnerability in Qualcomm Sd675 Firmware. Its CVSS base score is 8.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Client Execution (T1203); ranked in the top 36% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2021-1905 is a use-after-free vulnerability (CWE-416) caused by improper handling of memory mapping when multiple processes access the same region simultaneously. It affects a wide range of Qualcomm Snapdragon platforms, including Auto, Compute, Connectivity, Consumer IOT, Industrial IOT, Mobile, Voice & Music, and Wearables.

The flaw can be exploited by an unprivileged local attacker without user interaction. Successful exploitation grants the attacker full control over affected memory, enabling arbitrary code execution or other impacts that compromise confidentiality, integrity, and availability on the device.

Qualcomm's May 2021 security bulletin addresses the issue and provides mitigation guidance through updated firmware or software releases for the impacted Snapdragon components. The vulnerability is also catalogued by CISA as actively exploited in the wild.

EU & UK References

Vulnerability Data

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

CWE(s)
CWE-416
KEV Date Added
03 November 2021

Related Threats

MITRE ATT&CK Enterprise Techniques

T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
attack.mitre.org →
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
attack.mitre.org →
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2022-22071Same product: Qualcomm Apq8053both on KEV
CVE-2023-33063Same product: Qualcomm Apq8009both on KEV
CVE-2024-43047Same product: Qualcomm Qca6174Aboth on KEV
CVE-2025-27038Same product: Qualcomm Ar8031both on KEV
CVE-2024-21468Same product: Qualcomm Apq8017
CVE-2023-33120Same product: Qualcomm Apq8017
CVE-2023-33021Same product: Qualcomm Apq8064Au
CVE-2024-33060Same product: Qualcomm Aqt1000
CVE-2024-23373Same product: Qualcomm Aqt1000
CVE-2025-21424Same product: Qualcomm Aqt1000

Affected Assets

qualcomm
apq8009 firmware
all versions
qualcomm
apq8009w firmware
all versions
qualcomm
apq8017 firmware
all versions
qualcomm
apq8053 firmware
all versions
qualcomm
apq8064au firmware
all versions
qualcomm
apq8096au firmware
all versions
qualcomm
aqt1000 firmware
all versions
qualcomm
ar8031 firmware
all versions
qualcomm
ar8035 firmware
all versions
qualcomm
ar8151 firmware
all versions
+386 more product configuration(s) — see NVD for full list

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.4.3

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly incorporate memory-safety tooling and reviews that prevent most use-after-free defects.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover use-after-free issues via scanning or analysis but do not prevent their introduction.

PR.PS-02 partial match
prevents

Routine patching removes known use-after-free instances after they have been introduced in released software.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development can detect use-after-free bugs before release.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates memory-safety practices that reduce use-after-free defects.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify memory-management rules that mitigate use-after-free.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles include memory-safety design choices that limit use-after-free exposure.

A.8.28 Secure coding partial match
prevents

Secure coding standards directly prescribe avoidance of use-after-free patterns.

A.8.32 Change management partial match
prevents

Change-management processes help ensure memory-safety fixes are deployed consistently.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248592 OL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 8 (1 rule)
  • V-230279 RHEL 8 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416
RHEL 9 (1 rule)
  • V-257794 RHEL 9 must clear memory when it is freed to prevent use-after-free attacks. prevents CWE-416

References