Mozilla Firefox before 1.5.0.7, Thunderbird before 1.5.0.7, and SeaMonkey before 1.0.5 allows remote attackers to cause a denial of service (crash) via a malformed JavaScript regular expression that ends with a backslash in an unterminated character set ("[\\"), which leads to a buffer over-read.
CVE-2006-4566
This CVE was only ever scored under CVSS v2.0. NVD CVSS v2.0 base 5.0 — v2 rates that MEDIUM (v2 bands: LOW 0.0–3.9 / MEDIUM 4.0–6.9 / HIGH 7.0–10.0; v2 has no CRITICAL band). Vector AV:N/AC:L/Au:N/C:N/I:N/A:P. CVSS v2 is an older, coarser metric than v3.1/v4.0 (no Scope, no User Interaction, no Attack Requirements), so it is not directly comparable to a v3 or v4 score. NVD has never re-scored this record under v3. EPSS predicts 3.8% exploitation probability in the next 30 days, which is reflected in EG Risk but does not lift the v2 base. Confidence: LOW.
- Lower severity and no public exploit yet
A fix is available — apply it.
- CVSS v2.0 (legacy)
- 5.0MEDIUMNVD never assigned a CVSS v3 rating to this CVE
- EG Score
- 5.0(low)
- EG Risk
- 29(Track)EG Risk 29/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity50% × 45%Exploitation4% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 4%
- EPSS %ILE
- 90%
- KEV
- Not listed
Published
September 15, 2006
Last Modified
April 16, 2026
References (114)
- secalert@redhatftp://patches.sgi.com/support/free/security/advisories/20060901-01-P.asc
- secalert@redhathttp://secunia.com/advisories/21906
- secalert@redhathttp://secunia.com/advisories/21915
- secalert@redhathttp://secunia.com/advisories/21916
- secalert@redhathttp://secunia.com/advisories/21939
- secalert@redhathttp://secunia.com/advisories/21940
- secalert@redhathttp://secunia.com/advisories/21949
- secalert@redhathttp://secunia.com/advisories/21950
- secalert@redhathttp://secunia.com/advisories/22001
- secalert@redhathttp://secunia.com/advisories/22025
- secalert@redhathttp://secunia.com/advisories/22036
- secalert@redhathttp://secunia.com/advisories/22055
- secalert@redhathttp://secunia.com/advisories/22056
- secalert@redhathttp://secunia.com/advisories/22066
- secalert@redhathttp://secunia.com/advisories/22074
Patch Availability(6)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| ubuntu | libnss3 (1.5.dfsg+1.5.0.7-ubuntu0.6.06) @ dapper | 2026-05-31 | ubuntu |
| ubuntu | mozilla-thunderbird-locale-uk (1.5-ubuntu5.10) @ breezy | 2026-05-31 | ubuntu |
| ubuntu | mozilla-thunderbird (1.5.0.7-0ubuntu0.6.06) @ dapper | 2026-05-31 | ubuntu |
| redhat | thunderbird-0:1.5.0.7-0.1.el4 | 2006-09-15 | redhat |
| redhat | seamonkey-0:1.0.5-0.1.el4 | 2006-09-15 | redhat |
| redhat | firefox-0:1.5.0.7-0.1.el4 | 2006-09-15 | redhat |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Affected Packages
(7 across 5 ecosystems)
Debian:3.1(3)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| mozilla | 2:1.7.8-1 ... 2:1.7.8-1sarge7.2.2 (10 versions) | 2:1.7.8-1sarge7.3.1 | — |
| mozilla-firefox | 1.0.4-2 ... 1.0.4-2sarge9 (11 versions) | 1.0.4-2sarge12 | — |
| mozilla-thunderbird | 1.0.2-2 ... 1.0.2-2.sarge1.0.8b.2 (7 versions) | 1.0.2-2.sarge1.0.8c.1 | — |
Debian:11(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| thunderbird | — | 1.5.0.7-1 | — |
Debian:12(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| thunderbird | — | 1.5.0.7-1 | — |
Debian:13(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| thunderbird | — | 1.5.0.7-1 | — |
Debian:14(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| thunderbird | — | 1.5.0.7-1 | — |
All Vendor Advisories
(6)
Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.
- Red HatRHSA-2006:0675CRITICAL2006-09-15
RHSA-2006:0675 — Critical
- Red HatRHSA-2006:0676CRITICAL2006-09-15
RHSA-2006:0676 — Critical
- Red HatRHSA-2006:0677CRITICAL2006-09-15
RHSA-2006:0677 — Critical
- UbuntuUSN-350-1MEDIUM
Thunderbird vulnerabilities
- UbuntuUSN-351-1MEDIUM
firefox vulnerabilities
- UbuntuUSN-352-1MEDIUM
Thunderbird vulnerabilities
Data Freshness Timeline
(refreshed 3× in last 7d / 5× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-09-10 09:23 UTCEPSS rescore
- 2026-09-05 15:21 UTCEPSS rescore
- 2026-09-04 04:59 UTCEPSS rescore
- 2026-08-30 01:14 UTCEPSS rescore
- 2026-08-27 11:04 UTCOSV refresh
- 2026-08-11 00:31 UTCOSV refresh
- 2026-08-08 16:30 UTCEPSS rescore
- 2026-08-05 19:11 UTCEPSS rescore
- 2026-08-04 15:03 UTCEPSS rescore
- 2026-08-03 10:27 UTCEPSS rescore
- 2026-07-26 13:30 UTCEG score recompute▲ 5.00
- 2026-07-26 00:44 UTCOSV refresh
- 2026-07-24 14:11 UTCEPSS rescore
- 2026-07-23 00:51 UTCEG score recompute
- 2026-07-23 00:30 UTCEG score recompute
- 2026-07-22 23:55 UTCEG score recompute
- 2026-07-22 21:35 UTCEG score recompute
- 2026-07-20 17:02 UTCEPSS rescore
- 2026-07-18 09:59 UTCEPSS rescore
- 2026-07-16 16:58 UTCEPSS rescore
- 2026-07-15 16:53 UTCEPSS rescore
- 2026-07-15 01:55 UTCEPSS rescore
- 2026-07-13 22:25 UTCEPSS rescore
- 2026-07-13 06:07 UTCEPSS rescore
- 2026-07-13 06:07 UTCEPSS rescore
Show 64 moreShow fewer
- 2026-07-11 08:22 UTCEPSS rescore
- 2026-07-09 19:03 UTCEPSS rescore
- 2026-07-08 19:39 UTCOSV refresh
- 2026-07-08 15:09 UTCEPSS rescore
- 2026-07-06 02:19 UTCEPSS rescore
- 2026-07-06 02:19 UTCEPSS rescore
- 2026-07-04 06:26 UTCEPSS rescore
- 2026-07-02 14:00 UTCEPSS rescore
- 2026-07-01 15:01 UTCEPSS rescore
- 2026-06-27 03:04 UTCEPSS rescore
- 2026-06-25 13:46 UTCEPSS rescore
- 2026-06-24 14:01 UTCEPSS rescore
- 2026-06-24 14:01 UTCEPSS rescore
- 2026-06-23 21:29 UTCEPSS rescore
- 2026-06-23 21:29 UTCEPSS rescore
- 2026-06-22 14:22 UTCEPSS rescore
- 2026-06-21 01:56 UTCEPSS rescore
- 2026-06-20 07:12 UTCOSV refresh
- 2026-06-18 17:49 UTCEPSS rescore
- 2026-06-18 17:49 UTCEPSS rescore
- 2026-06-17 17:49 UTCEPSS rescore
- 2026-06-17 17:49 UTCEPSS rescore
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-15 17:44 UTCEPSS rescore
- 2026-06-14 23:13 UTCEPSS rescore
- 2026-06-13 22:56 UTCEPSS rescore
- 2026-06-12 23:08 UTCEPSS rescore
- 2026-06-11 13:55 UTCEPSS rescore
- 2026-06-10 22:14 UTCEPSS rescore
- 2026-06-10 13:17 UTCEPSS rescore
- 2026-06-06 13:44 UTCEPSS rescore
- 2026-06-06 13:44 UTCEPSS rescore
- 2026-06-05 22:43 UTCEPSS rescore
- 2026-06-05 06:07 UTCEPSS rescore
- 2026-06-05 06:07 UTCEPSS rescore
- 2026-06-04 13:09 UTCEPSS rescore
- 2026-06-04 13:09 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-05-31 06:46 UTCEG score recompute
- 2026-05-31 06:46 UTCVendor advisory
- 2026-05-31 06:45 UTCGHSA enrichment
- 2026-05-31 00:13 UTCEPSS rescore
- 2026-05-31 00:13 UTCEPSS rescore
- 2026-05-31 00:13 UTCEPSS rescore
- 2026-05-29 13:40 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-27 13:37 UTCEPSS rescore
- 2026-05-27 13:37 UTCEPSS rescore
- 2026-05-26 13:41 UTCEPSS rescore
- 2026-05-26 13:41 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-21 22:06 UTCOSV refresh
- 2026-05-20 22:36 UTCEPSS rescore
- 2026-05-20 22:36 UTCEPSS rescore
- 2026-05-20 11:20 UTCEPSS rescore
- 2026-05-20 11:20 UTCEPSS rescore
- 2026-05-18 21:29 UTCEPSS rescore
Frequently asked(4)
What is CVE-2006-4566?
When was CVE-2006-4566 disclosed?
Is CVE-2006-4566 actively exploited?
How do I remediate CVE-2006-4566?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2006-4566
Is Your Infrastructure Affected by CVE-2006-4566?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.