CVE-2005-0863: Cross-site scripting (XSS) vulnerability in PHPOpenChat v3.x allows remote attackers to inject arbitrary web s

Routine

MEDIUM 4.3DOWNGRADE

CVE-2005-0863 is a medium-severity flaw (CVSS 4.3) affecting phpopenchat. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

Cross-site scripting (XSS) vulnerability in PHPOpenChat v3.x allows remote attackers to inject arbitrary web script or HTML via (1) the chatter parameter to regulars.php or (2) the chatter, chatter1, chatter2, chatter3, or chatter4 parameters to register.php.

Why this priority

Public exploit reference

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

Risk facts

CVSS score	4.3 (Medium)
EPSS exploit chance	1.7% (top 23%)
CISA exploited list	No
Published	2005-05-02
Last modified	2026-06-16

Publisher (CNA): MITRE · Vendor: phpopenchat

Last updated 2026-06-16 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2005-05-02 04:00 UTCPublished CVE record published
2026-06-16 22:11 UTCUpdated Record last modified

phpopenchat phpopenchat DOWNGRADE

Affected: 3.0.0 · 3.0.1 · 3.0.2

Fixed in: no fixed release known

Safe to downgrade to: a release before 3.0.0

1. Check installed version

apt-cache policy phpopenchat || rpm -q phpopenchat || phpopenchat --version

2. No fixed release: DOWNGRADE to a release before 3.0.0 (Debian / Ubuntu)

apt-cache madison phpopenchat sudo apt install phpopenchat=<VERSION_BEFORE_3.0.0> sudo apt-mark hold phpopenchat

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

dnf --showduplicates list phpopenchat sudo dnf downgrade phpopenchat-<VERSION_BEFORE_3.0.0> sudo dnf versionlock add phpopenchat

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: PHPOpenChat 3.0.1 - Multiple HTML Injection Vulnerabilities

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-2005-0863?

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

Is CVE-2005-0863 being exploited?

CVE-2005-0863 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-2005-0863 affect?

CVE-2005-0863 affects phpopenchat. Severity is medium (CVSS 4.3). Cross-site scripting (XSS) vulnerability in PHPOpenChat v3.x allows remote attackers to inject arbitrary web script or HTML via (1) the chatter parameter to regulars.php or (2) the chatter, chatter1, chatter2, chatter3, or chatter4 paramete

How urgent is CVE-2005-0863?

Priority 39/100. Public exploit reference

Software pages

PHP vulnerabilities

Related CVEs

CVE-2006-4677 HIGH 7.5 UPGRADE PHP remote file inclusion vulnerability in contrib/yabbse/poc.php in phpopenchat before 3.0.2 allows remote at
CVE-2005-2545 MEDIUM 4.3 DOWNGRADE Multiple cross-site scripting (XSS) vulnerabilities in PHPOpenChat 3.0.2 allow remote attackers to inject arbi
CVE-2005-0862 HIGH 7.5 DOWNGRADE Multiple PHP remote file inclusion vulnerabilities in PHPOpenChat 3.0.1 and earlier allow remote attackers to

References

← Back to latest CVEs