CVE-2021-25827
CVE-2021-25827 is a critical-severity vulnerability in Emby 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-290.
Key facts
- Severity: Critical (CVSS 3.x base score 9.8)
- EPSS exploit prediction: 1% (71st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-290
- Affected product: Emby
- Published:
- Last modified:
Description
Emby Server < 4.7.12.0 is vulnerable to a login bypass attack by setting the X-Forwarded-For header to a local IP-address.
Frequently asked questions
- What is CVE-2021-25827?
- Emby Server < 4.7.12.0 is vulnerable to a login bypass attack by setting the X-Forwarded-For header to a local IP-address.
- How severe is CVE-2021-25827?
- CVE-2021-25827 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-2021-25827 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (71st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-25827?
- CVE-2021-25827 affects Emby. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-25827?
- 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-2021-25827 published?
- CVE-2021-25827 was published on 2023-06-28 and last updated on 2026-06-17.
References
- https://emby.media/community/index.php?/topic/98191-emby-server-46-released/
- https://github.com/EmbySupport/security/security/advisories/GHSA-fffj-6fr6-3fgf
- https://github.com/MediaBrowser/Emby/issues/3784
Affected products (1)
- cpe:2.3:a:emby:emby:*:*:*:*:*:*:*:*
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