CVE-2007-4990

CVE-2007-4990 is a high-severity vulnerability in X.org X Font Server with a CVSS 2.0 base score of 7.5. Its EPSS exploit-prediction score of 11% places it in the 95th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-189.

Key facts

• Severity: High (CVSS 2.0 base score 7.5)
• EPSS exploit prediction: 11% (95th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-189
• Affected product: X.org X Font Server
• Published: 2007-10-05
• Last modified: 2026-06-16

Description

The swap_char2b function in X.Org X Font Server (xfs) before 1.0.5 allows context-dependent attackers to execute arbitrary code via (1) QueryXBitmaps and (2) QueryXExtents protocol requests with crafted size values that specify an arbitrary number of bytes to be swapped on the heap, which triggers heap corruption.

Frequently asked questions

What is CVE-2007-4990?

The swap_char2b function in X.Org X Font Server (xfs) before 1.0.5 allows context-dependent attackers to execute arbitrary code via (1) QueryXBitmaps and (2) QueryXExtents protocol requests with crafted size values that specify an arbitrary number of bytes to be swapped on the heap, which triggers heap corruption.

How severe is CVE-2007-4990?

CVE-2007-4990 has a CVSS 2.0 base score of 7.5, rated high severity.

Is CVE-2007-4990 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 11% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2007-4990?

CVE-2007-4990 affects X.org X Font Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2007-4990?

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

When was CVE-2007-4990 published?

CVE-2007-4990 was published on 2007-10-05 and last updated on 2026-06-16.

References

• http://bugs.freedesktop.org/show_bug.cgi?id=12299
• http://bugs.gentoo.org/show_bug.cgi?id=194606
• http://docs.info.apple.com/article.html?artnum=307562
• http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c01323725
• http://labs.idefense.com/intelligence/vulnerabilities/display.php?id=602
• http://lists.apple.com/archives/security-announce/2008/Mar/msg00001.html
• http://lists.freedesktop.org/archives/xorg-announce/2007-October/000416.html
• http://secunia.com/advisories/27040
• http://secunia.com/advisories/27052
• http://secunia.com/advisories/27060
• http://secunia.com/advisories/27176
• http://secunia.com/advisories/27228
• http://secunia.com/advisories/27240
• http://secunia.com/advisories/27560
• http://secunia.com/advisories/28004
• http://secunia.com/advisories/28514
• http://secunia.com/advisories/28536
• http://secunia.com/advisories/28542
• http://secunia.com/advisories/29420
• http://security.gentoo.org/glsa/glsa-200710-11.xml
• http://sunsolve.sun.com/search/document.do?assetkey=1-26-103114-1
• http://sunsolve.sun.com/search/document.do?assetkey=1-66-200642-1
• http://www.mandriva.com/security/advisories?name=MDKSA-2007:210
• http://www.novell.com/linux/security/advisories/2007_54_xorg.html
• http://www.redhat.com/support/errata/RHSA-2008-0029.html
• http://www.redhat.com/support/errata/RHSA-2008-0030.html
• http://www.securityfocus.com/archive/1/481432/100/0/threaded
• http://www.securityfocus.com/bid/25898
• http://www.securitytracker.com/id?1018763
• http://www.vupen.com/english/advisories/2007/3337

Affected products (1)

• cpe:2.3:a:x.org:x_font_server:*:*:*:*:*:*:*:*

More vulnerabilities in X.org X Font Server

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