How severe is CVE-2026-21375?

CVE-2026-21375 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-21375 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-21375?

CVE-2026-21375 primarily affects Qualcomm Wcn3988 Firmware. In total, 35 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-21375?

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

Does CVE-2026-21375 have an EU (EUVD) identifier?

Yes. CVE-2026-21375 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-19330.

When was CVE-2026-21375 published?

CVE-2026-21375 was published on 2026-04-06 and last updated on 2026-06-17.

CVE-2026-21375

CVE-2026-21375 is a high-severity vulnerability in Qualcomm Wcn3988 Firmware with a CVSS 3.x base score of 7.8. 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-126.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 0% (1st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-19330
Weakness: CWE-126
Affected product: Qualcomm Wcn3988 Firmware
Published: 2026-04-06
Last modified: 2026-06-17

Description

Memory Corruption when accessing an output buffer without validating its size during IOCTL processing.

Frequently asked questions

What is CVE-2026-21375?: Memory Corruption when accessing an output buffer without validating its size during IOCTL processing.
How severe is CVE-2026-21375?: CVE-2026-21375 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-21375 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (1st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-21375?: CVE-2026-21375 primarily affects Qualcomm Wcn3988 Firmware. In total, 35 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-21375?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-21375 have an EU (EUVD) identifier?: Yes. CVE-2026-21375 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-19330.
When was CVE-2026-21375 published?: CVE-2026-21375 was published on 2026-04-06 and last updated on 2026-06-17.

References

https://docs.qualcomm.com/product/publicresources/securitybulletin/april-2026-bulletin.html

Affected products (35)

cpe:2.3:o:qualcomm:wcn3988_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wsa8830_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wsa8832_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wsa8835_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wsa8840_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wsa8845_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wsa8845h_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:x2000077_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:x2000086_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:x2000090_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:x2000092_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:x2000094_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:xg101002_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:xg101032_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:xg101039_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wcn3950_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wcd9385_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wcd9380_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wcd9378c_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wcd9375_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:wcd9370_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:snapdragon_ar1_gen_1_platform_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:snapdragon_8cx_gen_3_compute_platform_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:snapdragon_7c\+_gen_3_compute_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:snapdragon_662_mobile_platform_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:snapdragon_460_mobile_platform_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:sc8380xp_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:video_collaboration_vc3_platform_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:qcm6490_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:qcm5430_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:qca0000_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:fastconnect_7800_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:fastconnect_6900_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:fastconnect_6700_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:qualcomm:cologne_firmware:-:*:*:*:*:*:*:*

More vulnerabilities in Qualcomm Wcn3988 Firmware

CVE-2025-27034 — Critical (CVSS 9.8): Memory corruption while selecting the PLMN from SOR failed list.
CVE-2025-21483 — Critical (CVSS 9.8): Memory corruption when the UE receives an RTP packet from the network, during the reassembly of NALUs.
CVE-2023-43552 — Critical (CVSS 9.8): Memory corruption while processing MBSSID beacon containing several subelement IE.
CVE-2023-28582 — Critical (CVSS 9.8): Memory corruption in Data Modem while verifying hello-verify message during the DTLS handshake.
CVE-2023-33025 — Critical (CVSS 9.8): Memory corruption in Data Modem when a non-standard SDP body, during a VOLTE call.
CVE-2023-22388 — Critical (CVSS 9.8): Memory Corruption in Multi-mode Call Processor while processing bit mask API.

All CVEs affecting Qualcomm Wcn3988 Firmware →

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