SB2026101939 - Multiple vulnerabilities in LibreOffice
Published: October 19, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 7 vulnerabilities.
1) Heap-based buffer overflow (CVE-ID: CVE-2026-63274)
CWE-ID: CWE-122 - Heap-based Buffer Overflow
CVSSv4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error. A remote attacker can trick a victim to open a specially crafted PDF file, trigger a heap-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
2) Out-of-bounds read (CVE-ID: CVE-2026-63279)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to a boundary condition in PICT image import. A remote attacker can create a specially crafted file, trick the victim into opening it, trigger an out-of-bounds read error and read contents of memory on the system.
3) Information disclosure (CVE-ID: CVE-2026-63278)
CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor
CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to gain access to potentially sensitive information.
The vulnerability exists due to excessive data output by the application. A remote attacker can use package URLs to exfiltrate arbitrary INI file values and environment variables.
4) Stack-based buffer overflow (CVE-ID: CVE-2026-63276)
CWE-ID: CWE-121 - Stack-based buffer overflow
CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error in CFF to Type 1 font conversion. A remote unauthenticated attacker can trigger stack-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
5) Stack-based buffer overflow (CVE-ID: CVE-2026-63275)
CWE-ID: CWE-121 - Stack-based buffer overflow
CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error in CFF font hint handling. A remote unauthenticated attacker can trigger stack-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
6) Heap-based buffer overflow (CVE-ID: CVE-2026-63272)
CWE-ID: CWE-122 - Heap-based Buffer Overflow
CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error in WMF text record import. A remote attacker can pass specially crafted data to the application, trigger a heap-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
7) Heap-based buffer overflow (CVE-ID: CVE-2026-63273)
CWE-ID: CWE-122 - Heap-based Buffer Overflow
CVSSv4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error. A remote attacker can trick a victim to open a specially crafted PDF file, trigger a heap-based buffer overflow and execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Remediation
Install update from vendor's website.
References
- https://www.zerodayinitiative.com/advisories/ZDI-26-782/
- https://www.libreoffice.org/security/#cve-2026-63274
- https://www.libreoffice.org/about-us/security/advisories/cve-2026-63279
- https://www.libreoffice.org/about-us/security/advisories/cve-2026-63278
- https://www.libreoffice.org/about-us/security/advisories/cve-2026-63276
- https://www.libreoffice.org/about-us/security/advisories/cve-2026-63275
- https://www.libreoffice.org/about-us/security/advisories/cve-2026-63272
- https://www.zerodayinitiative.com/advisories/ZDI-26-783/
- https://www.libreoffice.org/security/#cve-2026-63273