What is CVE-2010-0420?

libpurple in Finch in Pidgin before 2.6.6, when an XMPP multi-user chat (MUC) room is used, does not properly parse nicknames containing sequences, which allows remote attackers to cause a denial of service (application crash) via a crafted nickname.

How severe is CVE-2010-0420?

CVE-2010-0420 has a CVSS 2.0 base score of 4.3, rated medium severity.

Is CVE-2010-0420 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2010-0420?

CVE-2010-0420 primarily affects Pidgin. In total, 29 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2010-0420?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2010-0420 published?

CVE-2010-0420 was published on 2010-02-24 and last updated on 2026-06-16.

CVE-2010-0420

CVE-2010-0420 is a medium-severity vulnerability in Pidgin with a CVSS 2.0 base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 2.0 base score 4.3)
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Pidgin
Published: 2010-02-24
Last modified: 2026-06-16

Description

libpurple in Finch in Pidgin before 2.6.6, when an XMPP multi-user chat (MUC) room is used, does not properly parse nicknames containing <br> sequences, which allows remote attackers to cause a denial of service (application crash) via a crafted nickname.

Frequently asked questions

What is CVE-2010-0420?: libpurple in Finch in Pidgin before 2.6.6, when an XMPP multi-user chat (MUC) room is used, does not properly parse nicknames containing <br> sequences, which allows remote attackers to cause a denial of service (application crash) via a crafted nickname.
How severe is CVE-2010-0420?: CVE-2010-0420 has a CVSS 2.0 base score of 4.3, rated medium severity.
Is CVE-2010-0420 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (85th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2010-0420?: CVE-2010-0420 primarily affects Pidgin. In total, 29 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2010-0420?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2010-0420 published?: CVE-2010-0420 was published on 2010-02-24 and last updated on 2026-06-16.

References

Affected products (29)

cpe:2.3:a:pidgin:pidgin:*:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.0.0:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.0.1:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.0.2:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.1.0:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.1.1:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.2.0:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.2.1:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.2.2:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.3.0:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.3.1:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.4.0:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.4.1:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.4.2:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.4.3:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.0:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.1:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.2:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.3:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.4:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.5:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.6:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.7:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.8:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.5.9:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.6.0:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.6.1:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.6.2:*:*:*:*:*:*:*
cpe:2.3:a:pidgin:pidgin:2.6.4:*:*:*:*:*:*:*

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