Rechercher
Contactez-nous Suivez-nous sur Twitter En francais English Language
 

De la Théorie à la pratique





















Freely subscribe to our NEWSLETTER

Newsletter FR

Newsletter EN

Vulnérabilités

Unsubscribe

Vigil@nce: GNU Enscript, buffer overflow via escape

October 2008 by Vigil@nce

An attacker can invite the victim to convert a malicious file with GNU Enscript in order to execute code on his computer.

- Gravity: 2/4
- Consequences: user access/rights
- Provenance: document
- Means of attack: 1 attack
- Ability of attacker: technician (2/4)
- Confidence: unique source (2/5)
- Diffusion of the vulnerable configuration: medium (2/3)
- Creation date: 23/10/2008

IMPACTED PRODUCTS

- Unix - plateform

DESCRIPTION

The GNU Enscript program converts a text file to PostScript, HTML or RTF.

The "-e" option of enscript enables the support of special patterns escaped by the null character (by default). For example, a text document can contain: \x00bgcolorr g b : indicates the background color \x00fontfontname : indicates the font to use etc.

The read_special_escape() function of the src/psgen.c file analyses these special patterns. When the "font’ pattern is used, the font name (its size can be up to 4096 bytes) is copied to a 512 bytes array, which creates an overflow.

An attacker can therefore create a text file containing a malicious "font" pattern, and invite the victim to open it with "enscript -e" in order to execute code on his computer.

CHARACTERISTICS

- Identifiers: BID-31858, CVE-2008-3863, VIGILANCE-VUL-8197
- Url: http://vigilance.aql.fr/vulnerability/8197




See previous articles

    

See next articles