qpdf: recursive calls can lead to a DoS in libqpdf/QPDFWriter.cc
Published Oct 6, 2018
3.3
LOWCVSS 3.0
EPSS 1.21%
Description
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.
Affected products
No data.
- 8.2.1
No data.
Red Hat Enterprise Linux 7
qpdf
Not affected
Red Hat Enterprise Linux 8
qpdf
Fix deferred
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 7 | qpdf | Not affected | n/a |
| Red Hat Enterprise Linux 8 | qpdf | Fix deferred | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
AV:N/AC:M/Au:N/C:N/I:N/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Table of values (9 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 1.21% (0.01209) | 67.29th | v5 (v2026.06.15) |
| Aug 23, 2026 | 2.14% (0.02142) | 80.41th | v5 (v2026.06.15) |
| Jul 20, 2024 | 0.10% (0.00102) | 42.15th | v3 (v2023.03.01) |
| Sep 3, 2023 | 0.10% (0.00102) | 40.89th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.09% (0.00090) | 36.94th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.05% (0.01055) | 52.13th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.05% (0.01055) | 27.52th | v2 (v2022.01.01) |
| Feb 3, 2022 | 0.65% (0.00651) | 18.22th | v5 (v2026.06.15) |
| Apr 14, 2021 | 0.65% (0.00651) | 0.00th | v1 |
References (6)
- https://access.redhat.com/security/cve/CVE-2018-18020 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1646389 Issue Tracking
- https://github.com/qpdf/qpdf/issues/243 ExploitIssue TrackingThird Party Advisory
- https://lists.debian.org/debian-lts-announce/2023/08/msg00037.html mailing-list
- https://nvd.nist.gov/vuln/detail/CVE-2018-18020
- https://www.cve.org/CVERecord?id=CVE-2018-18020
| Link | Providers | Tags |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2018-18020 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1646389 | Issue Tracking | |
| https://github.com/qpdf/qpdf/issues/243 | ExploitIssue TrackingThird Party Advisory | |
| https://lists.debian.org/debian-lts-announce/2023/08/msg00037.html | mailing-list | |
| https://nvd.nist.gov/vuln/detail/CVE-2018-18020 | ||
| https://www.cve.org/CVERecord?id=CVE-2018-18020 |
Change history (0)
No recorded changes yet.