CVE-2026-21640 json
HackerOne community member Faraz Ahmed (PakCyberbot) has reported a format string injection in the Revive Adserver settings.
published 9mo ago modified 4mo ago also EUVD-2026-3329
- cvss
- 2.7
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 16%
- public exploits
- 0
- none known
Summary
HackerOne community member Faraz Ahmed (PakCyberbot) has reported a format string injection in the Revive Adserver settings. When specific character combinations are used in a setting, the admin user console could be disabled due to a fatal PHP error.
Patch / fix
- revive-adserver revive_adserver 6.0.5
- revive adserver 6.0.5
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 9mo ago
Exploit prediction
0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 2.7 | CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L |
| NVD | 3.1 | 2.7 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N |
Affected products
- Revive Revive Adserver
Classification
- Weakness
-
- CWE-134 Use of Externally-Controlled Format String
References
-
hackerone.com
/reports/3445332
third-party-advisory
Sources
- CVE List CVE-2026-21640
- NVD CVE-2026-21640
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.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.