CVE-2010-1210: Mozilla Firefox

Medium severity, CVSS 4.3. EPSS: 1.3% chance of exploitation in the next 30 days.

intl/uconv/util/nsUnicodeDecodeHelper.cpp in Mozilla Firefox before 3.6.7 and Thunderbird before 3.1.1 inserts a U+FFFD sequence into text in certain circumstances involving undefined positions, which might make it easier for remote attackers to conduct cross-site scripting (XSS) attacks via crafted 8-bit text.

Affected products

• Mozilla Firefox: up to and including 3.6.6; version 0.1 only; version 0.2 only; version 0.3 only; version 0.4 only; version 0.5 only; …
• Mozilla Thunderbird: up to and including 3.1; version 0.1 only; version 0.2 only; version 0.3 only; version 0.4 only; version 0.5 only; …

Published 2010-07-30. Last modified 2026-06-16.