How severe is CVE-2021-1920?

CVE-2021-1920 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-1920 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1920?

CVE-2021-1920 primarily affects Qualcomm Apq8009 Firmware. In total, 171 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-1920?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-1920 published?

CVE-2021-1920 was published on 2021-09-08 and last updated on 2026-06-17.

CVE-2021-1920

CVE-2021-1920 is a critical-severity vulnerability in Qualcomm Apq8009 Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-191.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-191
Affected product: Qualcomm Apq8009 Firmware
Published: 2021-09-08
Last modified: 2026-06-17

Description

Integer underflow can occur due to improper handling of incoming RTCP packets in Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon IoT, Snapdragon Voice & Music, Snapdragon Wearables

Frequently asked questions

What is CVE-2021-1920?: Integer underflow can occur due to improper handling of incoming RTCP packets in Snapdragon Auto, Snapdragon Compute, Snapdragon Connectivity, Snapdragon Consumer IOT, Snapdragon Industrial IOT, Snapdragon IoT, Snapdragon Voice & Music, Snapdragon Wearables
How severe is CVE-2021-1920?: CVE-2021-1920 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-1920 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1920?: CVE-2021-1920 primarily affects Qualcomm Apq8009 Firmware. In total, 171 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-1920?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-1920 published?: CVE-2021-1920 was published on 2021-09-08 and last updated on 2026-06-17.

References

https://www.qualcomm.com/company/product-security/bulletins/august-2021-bulletin

Affected products (171)

cpe:2.3:o:qualcomm:apq8009_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:apq8009w_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:apq8017_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:apq8037_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:apq8053_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:apq8084_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:apq8096au_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:aqt1000_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:ar6003_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:csr6030_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:csrb31024_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm8207_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm8215_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm8215m_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm8615m_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9150_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9205_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9206_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9207_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9215_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9230_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9250_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9310_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9330_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9607_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9615_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9615m_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9625_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9628_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9630_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9635m_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9640_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9645_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9650_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:mdm9655_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:msm8108_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:msm8208_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:msm8209_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:msm8608_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:msm8909w_firmware:-:*:*:*:*:*:*:*

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