Ubuntu 16.04 LTS : QPDF vulnerabilities (USN-5026-2)

medium Nessus Plugin ID 152178
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The remote Ubuntu host is missing one or more security updates.


The remote Ubuntu 16.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-5026-2 advisory.

- In QPDF 8.2.1, in libqpdf/QPDFWriter.cc, QPDFWriter::unparseObject and QPDFWriter::unparseChild have recursive calls for a long time, which allows remote attackers to cause a denial of service via a crafted PDF file. (CVE-2018-18020)

- QPDF 9.x through 9.1.1 and 10.x through 10.0.4 has a heap-based buffer overflow in Pl_ASCII85Decoder::write (called from Pl_AES_PDF::flush and Pl_AES_PDF::finish) when a certain downstream write fails. (CVE-2021-36978)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.


Update the affected libqpdf-dev, libqpdf21 and / or qpdf packages.

See Also


Plugin Details

Severity: Medium

ID: 152178

File Name: ubuntu_USN-5026-2.nasl

Version: 1.2

Type: local

Agent: unix

Published: 8/2/2021

Updated: 8/2/2021

Dependencies: ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2021-36978


Risk Factor: Low

Score: 3.6


Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.2

Vector: AV:N/AC:M/Au:N/C:N/I:N/A:P

Temporal Vector: E:U/RL:OF/RC:C


Risk Factor: Medium

Base Score: 5.5

Temporal Score: 4.8

Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:16.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:libqpdf-dev, p-cpe:/a:canonical:ubuntu_linux:libqpdf21, p-cpe:/a:canonical:ubuntu_linux:qpdf

Required KB Items: Host/cpu, Host/Ubuntu, Host/Ubuntu/release, Host/Debian/dpkg-l

Exploit Ease: No known exploits are available

Patch Publication Date: 8/2/2021

Vulnerability Publication Date: 10/6/2018

Reference Information

CVE: CVE-2018-18020, CVE-2021-36978

USN: 5026-2