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Fencer Intel
critical 9.3

CVE-2026-21430 json

Emlog: CSRF chained with stored XSS leads to ATO

published 10mo ago modified 4mo ago also EUVD-2026-0757

cvss
9.3
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 8%
public exploits
0
none known

Summary

Emlog is an open source website building system. In version 2.5.23, article creation functionality is vulnerable to cross-site request forgery (CSRF). This can lead to a user being forced to post an article with arbitrary, attacker-controlled content. This, when combined with stored cross-site scripting, leads to account takeover. As of time of publication, no known patched versions are available.

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
10mo ago

Exploit prediction

0.19% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/emlog/emlog/security/advisories/GHSA-2g2w-vmg7-pq4q referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 7.0 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:P
CNA 4.0 7.0 CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
NVD 3.1 9.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

Affected products

  • emlog emlog

Classification

Weakness
  • CWE-352 Cross-Site Request Forgery
  • CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

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.