CVE-2009-0777: mozilla firefox Improper Input Validation
Vulnerability summary
CVE-2009-0777 is a medium (CVSS 5.8) Improper Input Validation vulnerability in mozilla firefox. EPSS estimates a 1.50% chance of exploitation in the next 30 days, higher than 74.2% of scored vulnerabilities.
Not severe (CVSS 5.8, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 3 · Related 2Timeline
- 05-03-2009PublishedVulnerability first disclosed.
- 07-08-2024Last modifiedVulnerability information updated.
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.
CVSS metrics
1 score · 1 source · 1 versionEPSS trend
Probability
1.50%
Chance of exploitation in the next 30 days
Percentile
74%
Versus all other CVEs
30-day change
No change 0.00 pp
From 1.50% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication (CVSS vector). Other conditions: not stated in public data.
Mozilla3 products
- firefox≤ 3.0.6 | 1.0 | 1.0.1 | 1.0.2 | 1.0.3 | 1.0.4 | 1.0.5 | 1.0.6 | 1.0.7 | 1.0.8 | 1.5 | 1.5.0.1 | 1.5.0.2 | 1.5.0.3 | 1.5.0.4 | 1.5.0.5 | 1.5.0.6 | 1.5.0.7 | 1.5.0.8 | 1.5.0.9 | 1.5.0.10 | 1.5.0.11 | 1.5.0.12 | 2.0 | 2.0.0.1 | 2.0.0.2 | 2.0.0.3 | 2.0.0.4 | 2.0.0.5 | 2.0.0.6 | 2.0.0.7 | 2.0.0.8 | 2.0.0.9 | 2.0.0.10 | 2.0.0.11 | 2.0.0.12 | 2.0.0.13 | 2.0.0.14 | 2.0.0.15 | 2.0.0.16 | 2.0.0.17 | 2.0.0.18 | 2.0.0.19 | 2.0.0.20 | 3.0 | 3.0.1 | 3.0.2 | 3.0.3 | 3.0.4 | 3.0.5
- seamonkey≤ 1.1.14 | 1.0 | 1.0.1 | 1.0.2 | 1.0.3 | 1.0.5 | 1.0.6 | 1.0.7 | 1.0.8 | 1.0.9 | 1.1 | 1.1:alpha | 1.1:beta | 1.1.1 | 1.1.2 | 1.1.3 | 1.1.4 | 1.1.5 | 1.1.6 | 1.1.7 | 1.1.8 | 1.1.9 | 1.1.10 | 1.1.11 | 1.1.12 | 1.1.13
- thunderbird≤ 2.0.0.20 | 2.0.0.0 | 2.0.0.4 | 2.0.0.5 | 2.0.0.6 | 2.0.0.9 | 2.0.0.12 | 2.0.0.14 | 2.0.0.16 | 2.0.0.17 | 2.0.0.18 | 2.0.0.19
1 vendor · 3 products
References
19 links- oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A11222VDB EntrySignatureX Refsource OVAL
- oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6157VDB EntrySignatureX Refsource OVAL
- oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6039VDB EntrySignatureX Refsource OVAL
- oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A6229VDB EntrySignatureX Refsource OVAL
Show all 19 references
- support.avaya.com/elmodocs2/security/ASA-2009-069.htmX Refsource CONFIRM
- bugzilla.mozilla.org/show_bug.cgi?id=452979X Refsource CONFIRM
- support.avaya.com/japple/…X Refsource CONFIRM
- oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A7435VDB EntrySignatureX Refsource OVAL