CVE-2021-25827 json
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.
published 3y ago modified 16d ago also EUVD-2021-12710
- cvss
- 9.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.5%
- EPSS 1.5% chance of exploitation in 30 days, percentile 74%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- emby emby 4.7.12.0
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Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- total
- Assessed
- last yr.
Exploit prediction
1.50% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/MediaBrowser/Emby/issues/3784 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Classification
- Weakness
-
- CWE-290 Authentication Bypass by Spoofing
References
-
github.com
/MediaBrowser/Emby/issues/3784
exploit, issue-tracking, third-party-advisory
-
emby.media
/community/index.php?/topic/98191-emby-server-46-released/
product
-
github.com
/EmbySupport/security/security/advisories/GHSA-fffj-6fr6-3fgf
not-applicable
Sources
- CVE List CVE-2021-25827
- NVD CVE-2021-25827
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.