How severe is CVE-2021-25263?

CVE-2021-25263 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-2021-25263 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25263?

CVE-2021-25263 affects Yandex Yandex Browser. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-25263?

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.

When was CVE-2021-25263 published?

CVE-2021-25263 was published on 2021-08-17 and last updated on 2026-06-17.

CVE-2021-25263

CVE-2021-25263 is a high-severity vulnerability in Yandex Yandex Browser 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-732.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 0% (22nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-732
Affected product: Yandex Yandex Browser
Published: 2021-08-17
Last modified: 2026-06-17

Description

Local privilege vulnerability in Yandex Browser for Windows prior to 21.9.0.390 allows a local, low privileged, attacker to execute arbitary code with the SYSTEM privileges through manipulating files in directory with insecure permissions during Yandex Browser update process.

Frequently asked questions

What is CVE-2021-25263?: Local privilege vulnerability in Yandex Browser for Windows prior to 21.9.0.390 allows a local, low privileged, attacker to execute arbitary code with the SYSTEM privileges through manipulating files in directory with insecure permissions during Yandex Browser update process.
How severe is CVE-2021-25263?: CVE-2021-25263 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-2021-25263 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (22nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25263?: CVE-2021-25263 affects Yandex Yandex Browser. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-25263?: 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.
When was CVE-2021-25263 published?: CVE-2021-25263 was published on 2021-08-17 and last updated on 2026-06-17.

References

https://yandex.com/bugbounty/i/hall-of-fame-browser/

Affected products (1)

cpe:2.3:a:yandex:yandex_browser:*:*:*:*:*:windows:*:*

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