How severe is CVE-2017-10966?

CVE-2017-10966 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2017-10966 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-2017-10966?

CVE-2017-10966 affects Irssi. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2017-10966?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2017-10966 published?

CVE-2017-10966 was published on 2017-07-07 and last updated on 2026-06-17.

CVE-2017-10966

CVE-2017-10966 is a critical-severity vulnerability in Irssi with a CVSS 3.x base score of 9.8. 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-416.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (85th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Irssi
Published: 2017-07-07
Last modified: 2026-06-17

Description

An issue was discovered in Irssi before 1.0.4. While updating the internal nick list, Irssi could incorrectly use the GHashTable interface and free the nick while updating it. This would then result in use-after-free conditions on each access of the hash table.

Frequently asked questions

What is CVE-2017-10966?: An issue was discovered in Irssi before 1.0.4. While updating the internal nick list, Irssi could incorrectly use the GHashTable interface and free the nick while updating it. This would then result in use-after-free conditions on each access of the hash table.
How severe is CVE-2017-10966?: CVE-2017-10966 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2017-10966 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-2017-10966?: CVE-2017-10966 affects Irssi. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2017-10966?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2017-10966 published?: CVE-2017-10966 was published on 2017-07-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:irssi:irssi:*:*:*:*:*:*:*:*

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