How severe is CVE-1999-0241?

CVE-1999-0241 has a CVSS 2.0 base score of 10.0, rated critical severity.

Is CVE-1999-0241 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-1999-0241?

CVE-1999-0241 primarily affects Xfree86 Project X11r6. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-1999-0241?

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-1999-0241 published?

CVE-1999-0241 was published on 1995-11-01 and last updated on 2026-06-16.

CVE-1999-0241

CVE-1999-0241 is a critical-severity vulnerability in Xfree86 Project X11r6 with a CVSS 2.0 base score of 10.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Critical (CVSS 2.0 base score 10.0)
EPSS exploit prediction: 4% (90th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Xfree86 Project X11r6
Published: 1995-11-01
Last modified: 2026-06-16

Description

Guessable magic cookies in X Windows allows remote attackers to execute commands, e.g. through xterm.

Frequently asked questions

What is CVE-1999-0241?: Guessable magic cookies in X Windows allows remote attackers to execute commands, e.g. through xterm.
How severe is CVE-1999-0241?: CVE-1999-0241 has a CVSS 2.0 base score of 10.0, rated critical severity.
Is CVE-1999-0241 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-1999-0241?: CVE-1999-0241 primarily affects Xfree86 Project X11r6. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-1999-0241?: 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-1999-0241 published?: CVE-1999-0241 was published on 1995-11-01 and last updated on 2026-06-16.

References

https://exchange.xforce.ibmcloud.com/vulnerabilities/CVE-1999-0241

Affected products (6)

cpe:2.3:a:xfree86_project:x11r6:*:*:*:*:*:*:*:*
cpe:2.3:o:sgi:irix:*:*:*:*:*:*:*:*
cpe:2.3:o:sun:solaris:2.5:*:x86:*:*:*:*:*
cpe:2.3:o:sun:solaris:2.5.1:*:x86:*:*:*:*:*
cpe:2.3:o:sun:solaris:7.0:*:x86:*:*:*:*:*
cpe:2.3:o:sun:sunos:-:*:*:*:*:*:*:*

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CVE-2005-0605 — High (CVSS 7.5): scan.c for LibXPM may allow attackers to execute arbitrary code via a negative bitmap_unit value that leads to a buffer…

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