How severe is CVE-2021-25434?

CVE-2021-25434 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-2021-25434 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25434?

CVE-2021-25434 affects Linux Tizen. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-25434?

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-2021-25434 published?

CVE-2021-25434 was published on 2021-07-08 and last updated on 2026-06-17.

CVE-2021-25434

CVE-2021-25434 is a critical-severity vulnerability in Linux Tizen 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-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (74th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Linux Tizen
Published: 2021-07-08
Last modified: 2026-06-17

Description

Improper input validation vulnerability in Tizen bootloader prior to Firmware update JUL-2021 Release allows arbitrary code execution using param partition in wireless firmware download mode.

Frequently asked questions

What is CVE-2021-25434?: Improper input validation vulnerability in Tizen bootloader prior to Firmware update JUL-2021 Release allows arbitrary code execution using param partition in wireless firmware download mode.
How severe is CVE-2021-25434?: CVE-2021-25434 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-2021-25434 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (74th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25434?: CVE-2021-25434 affects Linux Tizen. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-25434?: 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-2021-25434 published?: CVE-2021-25434 was published on 2021-07-08 and last updated on 2026-06-17.

References

https://security.samsungmobile.com/serviceWeb.smsb?year=2021&month=7

Affected products (1)

cpe:2.3:o:linux:tizen:*:*:*:*:*:*:*:*

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