Threats / Laravel / CVE-2021-3129
CVE-2021-3129
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Laravel Ignition vulnerability
Laravel Ignition contains a file upload vulnerability allowing unauthenticated remote code execution through insecure file handling functions, enabling arbitrary code execution on affected systems.
Verdict
Today item, not a backlog item.
Unauthenticated attackers can upload malicious files and execute arbitrary code on servers running vulnerable Laravel Ignition versions. The high EPSS score and active exploitation in ransomware campaigns indicate severe real-world risk requiring immediate patching.
CISA KEV Yes · 2023-09-183Ransomware use Flagged3EPSS 0.99943 (verify live)4Exploit Weaponized · public PoC5
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
957 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-09-18), flagged for known ransomware use.
Probability (EPSS)
EPSS 0.99943 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Laravel, Ignition. Confirm exact fixed builds in the vendor advisory.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious file and upload it through the vulnerable endpoint without authentication.
Business
Attackers gain initial access to the web application with no credentials required.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I leverage insecure file_get_contents() and file_put_contents() functions to write executable code to the server.
Business
Arbitrary code execution is achieved on the underlying server infrastructure.
3
Lateral reach — past segmentation narrative 3
Attacker
I execute system commands and establish persistence or deploy ransomware payloads.
Business
Complete system compromise occurs, leading to data encryption, exfiltration, or operational disruption.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05