CVE-2020-35416: Multiple cross-site scripting (XSS) vulnerabilities exist in PHPJabbers Appointment Scheduler 2.3, in the inde

This month

MEDIUM 6.1DOWNGRADE

CVE-2020-35416 is a medium-severity flaw (CVSS 6.1) affecting phpjabbers appointment scheduler. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Multiple cross-site scripting (XSS) vulnerabilities exist in PHPJabbers Appointment Scheduler 2.3, in the index.php admin login webpage (with different request parameters), allows remote attackers to inject arbitrary web script or HTML.

Why this priority

Public exploit reference

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	6.1 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	Required
EPSS exploit chance	2.7% (top 14%)
CISA exploited list	No
Weakness	CWE-79
Published	2020-12-15
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: onlineonly

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2020-12-15 21:15 UTCPublished CVE record published
2026-06-17 03:13 UTCUpdated Record last modified

onlineonly phpjabbers appointment scheduler DOWNGRADE

Affected: 2.3

Fixed in: no fixed release known

Safe to downgrade to: a release before 2.3

1. Check installed version

apt-cache policy phpjabbers-appointment-scheduler || rpm -q phpjabbers-appointment-scheduler || phpjabbers-appointment-scheduler --version

2. No fixed release: DOWNGRADE to a release before 2.3 (Debian / Ubuntu)

apt-cache madison phpjabbers-appointment-scheduler sudo apt install phpjabbers-appointment-scheduler=<VERSION_BEFORE_2.3> sudo apt-mark hold phpjabbers-appointment-scheduler

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list phpjabbers-appointment-scheduler sudo dnf downgrade phpjabbers-appointment-scheduler-<VERSION_BEFORE_2.3> sudo dnf versionlock add phpjabbers-appointment-scheduler

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Public exploits and detection

Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.

Exploit-DB: PHPJabbers Appointment Scheduler 2.3 - Reflected XSS (Cross-Site Scripting)

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2020-35416?

phpjabbers appointment scheduler: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2020-35416 being exploited?

CVE-2020-35416 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2020-35416 affect?

CVE-2020-35416 affects phpjabbers appointment scheduler. Severity is medium (CVSS 6.1). Multiple cross-site scripting (XSS) vulnerabilities exist in PHPJabbers Appointment Scheduler 2.3, in the index.php admin login webpage (with different request parameters), allows remote attackers to inject arbitrary web script or HTML.

How urgent is CVE-2020-35416?

Priority 48/100. Public exploit reference

Software pages

PHP vulnerabilities

References

← Back to latest CVEs