CVE-2018-18651 — An issue was discovered in Xpdf 4

An issue was discovered in Xpdf 4.00. catalog->getNumPages() in AcroForm.cc allows attackers to launch a denial of service (hang caused by large loop) via a specific pdf file, as demonstrated by pdftohtml. This is mainly caused by a large number after the /Count field in the f

01What is this vulnerability?

An issue was discovered in Xpdf 4.00. catalog->getNumPages() in AcroForm.cc allows attackers to launch a denial of service (hang caused by large loop) via a specific pdf file, as demonstrated by pdftohtml. This is mainly caused by a large number after the /Count field in the file.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2018-10-25T13:00:00.000Z
• Last modified: 2024-09-16T22:19:56.190Z

09References

• forum.xpdfreader.com — https://forum.xpdfreader.com/viewtopic.php?f=3&t=41219&p=41747#p41747