GNU Project UnRTF up to 0.21.11 RTF File out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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5.3$0-$5k5.86-

Summaryinfo

A vulnerability classified as problematic was found in GNU Project UnRTF up to 0.21.11. The impacted element is an unknown function of the component RTF File Handler. Such manipulation leads to out-of-bounds write. This vulnerability is referenced as CVE-2026-109831. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in GNU Project UnRTF up to 0.21.11. Affected by this issue is an unknown function of the component RTF File Handler. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is integrity, and availability. CVE summarizes:

UnRTF by GNU Project is vulnerable to out-of-bounds write. If a user opens an RTF file crafted by an attacker, it may lead to a denial-of-service (DoS) condition.

The advisory is shared for download at savannah.gnu.org. This vulnerability is handled as CVE-2026-109831 since 10/13/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available.

Upgrading to version 0.21.12 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.4
VulDB Temp Score: 5.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.4
CNA Vector (jpcert): 🔒

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: UnRTF 0.21.12

Timelineinfo

10/13/2026 CVE reserved
10/20/2026 +7 days Advisory disclosed
10/20/2026 +0 days VulDB entry created
10/20/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: savannah.gnu.org
Status: Confirmed

CVE: CVE-2026-109831 (🔒)
GCVE (CVE): GCVE-0-2026-109831
GCVE (VulDB): GCVE-100-422660

Entryinfo

Created: 10/20/2026 07:08
Changes: 10/20/2026 07:08 (76)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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