CVE-2011-2371
CriticalPublic exploitMozilla Integer overflow and arbitrary code execution (MFSA 2011-22)
Published Jun 21, 2011 · Updated Mar 9, 2026
Key Facts
Patch immediately- CVE-2011-2371 is a critical-severity vulnerability (CVSS 10.0 v2) affecting Firefox (Mozilla), Seamonkey (Mozilla), Thunderbird (Mozilla) and 22 more products.
- It is not listed in any known-exploited vulnerabilities catalog. Public exploit code is available.
- EPSS estimates a 76% probability of exploitation in the next 30 days.
- Fixed versions are available, including Firefox 0:3.6.18-1.el5_6, Firefox 0:3.6.18-1.el6_1, Firefox 0:3.6.18-2.el4.
- Brandefense priority: patch immediately, because it is very likely to be exploited soon.
CVSS v2
10.0
AV:N/AC:L/Au:N/C:C/I:C/A:C
EPSS (30-day exploit likelihood)
76%
Higher than 99.5% of all scored CVEs
Exploited in the wild
No known
Not in a known-exploited catalog
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2011-2371 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
Description
Integer overflow in the Array.reduceRight method in Mozilla Firefox before 3.6.18 and 4.x through 4.0.1, Thunderbird before 3.1.11, and SeaMonkey through 2.0.14 allows remote attackers to execute arbitrary code via vectors involving a long JavaScript Array object.
Affected Products
303 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| FirefoxMozilla | 1.0, 1.0.1, 1.0.2, 1.0.3, 1.0.4, 1.0.5, 1.0.6, 1.0.7 | 3.6.17 |
| SeamonkeyMozilla | 1.0, 1.0.1, 1.0.2, 1.0.3, 1.0.4, 1.0.5, 1.0.6, 1.0.7 | 0:1.0.9-71.el4 |
| ThunderbirdMozilla | 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.7.1 | 3.1.10 |
| iceapedebian | See advisory | 2.0.11-6 |
| icedovedebian | See advisory | 3.0.11-1+squeeze3 |
Patched Releases
Firefox
0:3.6.18-1.el5_6, 0:3.6.18-1.el6_1, 0:3.6.18-2.el4, 3.6.18-1.0.1.el5_6, 3.6.18-1.0.1.el6_1, 3.6.17
firefox-esr
128.5.1-1.1
firefox-esr-branding-upstream
128.5.1-1.1
firefox-esr-translations-common
128.5.1-1.1
firefox-esr-translations-other
128.5.1-1.1
iceape
2.0.11-6
icedove
3.0.11-1+squeeze3
iceweasel
3.5.16-8
Thunderbird
3.1.10, 0:1.5.0.12-39.el4, 0:2.0.0.24-18.el5_6
MozillaFirefox
50.1.0-1.1
MozillaFirefox-branding-upstream
50.1.0-1.1
MozillaFirefox-buildsymbols
50.1.0-1.1
MozillaFirefox-devel
50.1.0-1.1
MozillaFirefox-translations-common
50.1.0-1.1
MozillaFirefox-translations-other
50.1.0-1.1
MozillaThunderbird
45.5.1-1.1
MozillaThunderbird-buildsymbols
45.5.1-1.1
MozillaThunderbird-devel
45.5.1-1.1
MozillaThunderbird-translations-common
45.5.1-1.1
MozillaThunderbird-translations-other
45.5.1-1.1
Seamonkey
0:1.0.9-71.el4, 2.40-6.1
seamonkey-dom-inspector
2.40-6.1
seamonkey-irc
2.40-6.1
seamonkey-translations-common
2.40-6.1
seamonkey-translations-other
2.40-6.1
Timeline
Publicly disclosed
Jun 21, 2011
Last updated
Mar 9, 2026
Weakness Type
- CWE-189
- CWE-190 Integer Overflow or Wraparound
References
- advisoryRHSA-2011:0885
- advisoryRHSA-2011:0887
- advisoryRHSA-2011:0888
- advisoryhttp://www.mozilla.org/security/announce/2011/mfsa2011-22.html
- exploitMSF mozilla_reduceright.rb
FAQ
Common Questions.
Integer overflow in the Array.reduceRight method in Mozilla Firefox before 3.6.18 and 4.x through 4.0.1, Thunderbird before 3.1.11, and SeaMonkey through 2.0.14 allows remote attackers to execute arbitrary code via vectors involving a long JavaScript Array object.
Affected: Firefox (Mozilla) versions 1.0, 1.0.1, 1.0.2, 1.0.3, 1.0.4, 1.0.5, 1.0.6, 1.0.7; Seamonkey (Mozilla) versions 1.0, 1.0.1, 1.0.2, 1.0.3, 1.0.4, 1.0.5, 1.0.6, 1.0.7; Thunderbird (Mozilla) versions 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.7.1, among others. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
Public exploit code is available.
Fixed versions are available, including Firefox 0:3.6.18-1.el5_6, Firefox 0:3.6.18-1.el6_1, Firefox 0:3.6.18-2.el4.
Brandefense priority: patch immediately, because it is very likely to be exploited soon.
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