How severe is CVE-2018-18651?

CVE-2018-18651 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-18651 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-18651?

CVE-2018-18651 affects Xpdfreader Xpdf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-18651?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-18651 published?

CVE-2018-18651 was published on 2018-10-25 and last updated on 2026-06-17.

CVE-2018-18651

CVE-2018-18651 is a medium-severity vulnerability in Xpdfreader Xpdf with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-834.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-834
Affected product: Xpdfreader Xpdf
Published: 2018-10-25
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2018-18651?: 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.
How severe is CVE-2018-18651?: CVE-2018-18651 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-18651 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-18651?: CVE-2018-18651 affects Xpdfreader Xpdf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-18651?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-18651 published?: CVE-2018-18651 was published on 2018-10-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:xpdfreader:xpdf:4.00:*:*:*:*:*:*:*

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