SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2026-43880

In versions up to and including 29.0, objects/sendEmail.json.php exposes two branches depending on whether contactForm=1 is submitted.

MEDIUM 5.3EPSS 0.29%

Does this matter?

Lower severity and a low EPSS score (0.29%). Track it; it rarely justifies an emergency change on its own.

Description

WWBN AVideo is an open source video platform. In versions up to and including 29.0, objects/sendEmail.json.php exposes two branches depending on whether contactForm=1 is submitted. When the parameter is omitted, the endpoint sets $sendTo to an attacker-supplied email and, for unauthenticated callers, uses the site's own contact email as the message From:/Reply-To:. The endpoint is explicitly allow-listed as a "public write action" in objects/functionsSecurity.php (line 885), so it requires no authentication or CSRF token. An unauthenticated attacker (solving a captcha) can force the site's own SMTP infrastructure to send attacker-composed emails to arbitrary recipients with the site's legitimate sender address, passing SPF/DKIM/DMARC for the site's domain — ideal for targeted phishing and brand impersonation. Commit 4e3709895857a5857f0edb46b0ee984de0d9e1a2 contains an updated fix.

CVSS 3.1
5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS
0.29% probability · 21th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-940
Source
security-advisories@github.com
EPSS trend
0%3%5%27 October 2026: 0.29%27 October 202627 October 2026

EPSS 0.3% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.