PatchTheCVECVE-2016-7966: Through a malicious URL that contained a quote character it was possible to inject HTML code in KMail's plaint
CVE-2016-7966 is a high-severity flaw (CVSS 7.3) affecting kmail, debian linux, fedora. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Through a malicious URL that contained a quote character it was possible to inject HTML code in KMail's plaintext viewer. Due to the parser used on the URL it was not possible to include the equal sign (=) or a space into the injected HTML, which greatly reduces the available HTML functionality. Although it is possible to include an HTML comment indicator to hide content.
Why this priority
- High severity
- Remotely exploitable, no login, no user action
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.3 (High) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 2.3% (top 16%) |
| CISA exploited list | No |
| Weakness | CWE-94 |
| Published | 2016-12-23 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
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-2016-7966?
kmail: upgrade to newer than 4.4.0; debian linux: mitigate or apply the listed mitigation; fedora: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2016-7966 being exploited?
CVE-2016-7966 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-2016-7966 affect?
CVE-2016-7966 affects kmail, debian linux, fedora. Severity is high (CVSS 7.3). Through a malicious URL that contained a quote character it was possible to inject HTML code in KMail's plaintext viewer. Due to the parser used on the URL it was not possible to include the equal sign (=) or a space into the injected HTML,
How urgent is CVE-2016-7966?
Priority 56/100. High severity; Remotely exploitable, no login, no user action; On your watchlist
Software pages
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