How severe is CVE-2019-15717?

CVE-2019-15717 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-2019-15717 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-15717?

CVE-2019-15717 primarily affects Irssi. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-15717?

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-2019-15717 published?

CVE-2019-15717 was published on 2019-08-29 and last updated on 2026-06-17.

CVE-2019-15717

CVE-2019-15717 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: 2% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Irssi
Published: 2019-08-29
Last modified: 2026-06-17

Description

Irssi 1.2.x before 1.2.2 has a use-after-free if the IRC server sends a double CAP.

Frequently asked questions

What is CVE-2019-15717?: Irssi 1.2.x before 1.2.2 has a use-after-free if the IRC server sends a double CAP.
How severe is CVE-2019-15717?: CVE-2019-15717 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-2019-15717 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-15717?: CVE-2019-15717 primarily affects Irssi. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-15717?: 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-2019-15717 published?: CVE-2019-15717 was published on 2019-08-29 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:irssi:irssi:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:19.04:*:*:*:*:*:*:*

More vulnerabilities in Irssi

CVE-2002-1840 — Critical (CVSS 10.0): irssi IRC client 0.8.4, when downloaded after 14-March-2002, could contain a backdoor in the configuration file, which…
CVE-2019-5882 — Critical (CVSS 9.8): Irssi 1.1.x before 1.1.2 has a use after free when hidden lines are expired from the scroll buffer.
CVE-2018-7054 — Critical (CVSS 9.8): An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. There is a use-after-free when a server is…
CVE-2018-7053 — Critical (CVSS 9.8): An issue was discovered in Irssi before 1.0.7 and 1.1.x before 1.1.1. There is a use-after-free when SASL messages are…
CVE-2018-5208 — Critical (CVSS 9.8): In Irssi before 1.0.6, a calculation error in the completion code could cause a heap buffer overflow when completing…
CVE-2018-5206 — Critical (CVSS 9.8): When the channel topic is set without specifying a sender, Irssi before 1.0.6 may dereference a NULL pointer.

All CVEs affecting Irssi →

Other CWE-416 (Use After Free) vulnerabilities

CVE-2026-13782 — Critical (CVSS 10.0): Use after free in Browser in Google Chrome prior to 150.0.7871.47 allowed a remote attacker who had compromised the…
CVE-2026-4725 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 149…
CVE-2026-4688 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox…
CVE-2025-24085 — Critical (CVSS 10.0): A use after free issue was addressed with improved memory management. This issue is fixed in iOS 18.3 and iPadOS 18.3,…
CVE-2024-43102 — Critical (CVSS 10.0): Concurrent removals of certain anonymous shared memory mappings by using the UMTX_SHM_DESTROY sub-request of…
CVE-2021-32495 — Critical (CVSS 10.0): Radare2 has a use-after-free vulnerability in pyc parser's get_none_object function. Attacker can read freed memory…

Browse all CWE-416 (Use After Free) vulnerabilities →