Emlog: CSRF chained with stored XSS leads to ATO

published 2026-01-02 10 mo ago modified 2026-06-17 4 mo 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

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.

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 10 mo ago (2026-01-05)

Exploit prediction

0.18% chance of exploitation in the next 30 days, higher than 8% of all scored CVEs (FIRST EPSS, 2026-11-08).

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

github.com /emlog/emlog/security/advisories/GHSA-2g2w-vmg7-pq4q
exploit, vendor-advisory

Sources

CVE List CVE-2026-21430
NVD CVE-2026-21430

Fencer Vulns 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.

Summary