Bug 1082842 – VUL-1: CVE-2018-7454: xpdf: A NULL pointer dereference in XFAForm::scanFields in XFAForm.cc allows attackers to launch denial of service via a specific pdf file

Bug 1082842 - (CVE-2018-7454) VUL-1: CVE-2018-7454: xpdf: A NULL pointer dereference in XFAForm::scanFields in XFAForm.cc allows attackers to launch denial of service via a specific pdf file

(CVE-2018-7454)
Summary:	VUL-1: CVE-2018-7454: xpdf: A NULL pointer dereference in XFAForm::scanFields...

Status:	NEW

Classification:	Novell Products
Product:	SUSE Security Incidents
Classification:	Novell Products
Component:	Incidents
Version:	unspecified
Hardware:	Other Other

Priority:	P4 - Low Severity: Normal
Target Milestone:	---
Assigned To:	Peter Simons
QA Contact:	Security Team bot

URL:	https://smash.suse.de/issue/200814/
Whiteboard:	CVSSv3:SUSE:CVE-2018-7454:3.3:(AV:L/...
Keywords:

Depends on:
Blocks:	1133493
	Show dependency tree / graph

Create test case

Clone This Bug

Reported:	2018-02-26 13:08 UTC by Karol Babioch
Modified:	2020-06-29 06:32 UTC (History)
CC List:	1 user (show)

See Also:
Found By:	Security Response Team
Services Priority:
Business Priority:
Blocker:	---
Marketing QA Status:	---
IT Deployment:	---

Attachments
Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.

Description Karol Babioch 2018-02-26 13:08:49 UTC

CVE-2018-7454

A NULL pointer dereference in XFAForm::scanFields in XFAForm.cc in xpdf 4.00
allows attackers to launch denial of service via a specific pdf file, as
demonstrated by pdftohtml.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2018-7454
http://www.cvedetails.com/cve/CVE-2018-7454/

Comment 1 Peter Simons 2018-06-21 09:14:54 UTC

No fix for this issue was published. According to the web forum, upstream tried to remedy this issue by

> adding a test for nComps==0 when reading the SIZ segment

..., but this turned out to be insufficient. After some back and forth, the solution apparently is to disable 0 page PDF files altogether:

> Zero-page PDF files are kind of an odd case. I'll add a test in XFAForm::load that bails out early if nPages==0.

I looked at the code of XFAForm::load() in the 4.00 release, trying to re-implement the fix, but unfortunately there is no obvious way to write that test. (nPages is an attribute deep inside of a XFAForm object, so the object has to be constructed already before I can access it, which seems too late for the test to be meaningful).

Upstream was asked whether they'll release the fix -- or a new version that contains it --, and they said:

> This will be in the next release. I don't have a schedule for that yet.

That was over a year ago.