CVE Vulnerabilities

CVE-2018-7173

Encoding Error

Published: Feb 15, 2018 | Modified: Nov 21, 2024
CVSS 3.x
5.5
MEDIUM
Source:
NVD
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CVSS 2.x
4.3 MEDIUM
AV:N/AC:M/Au:N/C:N/I:N/A:P
RedHat/V2
RedHat/V3
Ubuntu
NEGLIGIBLE

A large loop in JBIG2Stream::readSymbolDictSeg in xpdf 4.00 allows an attacker to cause denial of service via a specific file due to inappropriate decoding.

Weakness

The product does not properly encode or decode the data, resulting in unexpected values.

Affected Software

Name Vendor Start Version End Version
Xpdf Xpdfreader 4.00 (including) 4.00 (including)
Ipe Ubuntu artful *
Ipe Ubuntu bionic *
Ipe Ubuntu cosmic *
Ipe Ubuntu disco *
Ipe Ubuntu eoan *
Ipe Ubuntu groovy *
Ipe Ubuntu hirsute *
Ipe Ubuntu impish *
Ipe Ubuntu kinetic *
Ipe Ubuntu lunar *
Ipe Ubuntu mantic *
Ipe Ubuntu trusty *
Ipe Ubuntu xenial *
Libextractor Ubuntu artful *
Libextractor Ubuntu cosmic *
Libextractor Ubuntu disco *
Libextractor Ubuntu eoan *
Libextractor Ubuntu groovy *
Libextractor Ubuntu hirsute *
Libextractor Ubuntu impish *
Libextractor Ubuntu trusty *
Libextractor Ubuntu xenial *
Xpdf Ubuntu artful *
Xpdf Ubuntu bionic *
Xpdf Ubuntu cosmic *
Xpdf Ubuntu devel *
Xpdf Ubuntu disco *
Xpdf Ubuntu eoan *
Xpdf Ubuntu esm-apps/bionic *
Xpdf Ubuntu esm-apps/jammy *
Xpdf Ubuntu esm-apps/noble *
Xpdf Ubuntu esm-apps/xenial *
Xpdf Ubuntu hirsute *
Xpdf Ubuntu impish *
Xpdf Ubuntu jammy *
Xpdf Ubuntu kinetic *
Xpdf Ubuntu lunar *
Xpdf Ubuntu mantic *
Xpdf Ubuntu noble *
Xpdf Ubuntu oracular *
Xpdf Ubuntu trusty *
Xpdf Ubuntu xenial *

Potential Mitigations

  • Assume all input is malicious. Use an “accept known good” input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
  • When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, “boat” may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as “red” or “blue.”
  • Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code’s environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.

References