CVE-2026-54531
published 2026-06-22CVE-2026-54531: pypdf is a free and open-source pure-python PDF library. Prior to 6.13.0, an attacker who uses this vulnerability can craft a PDF which leads to an infinite…
PriorityP423medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.12%
2.4th percentile
pypdf is a free and open-source pure-python PDF library. Prior to 6.13.0, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires merging a file with outlines into a writer. This vulnerability is fixed in 6.13.0.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| py-pdf | pypdf | < 6.13.0 | 6.13.0 |
| pypdf_project | pypdf | < 6.13.0 | 6.13.0 |
| pypdf_project | pypdf | >= 0 < 6.13.0 | 6.13.0 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvdv4.06.9MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
vendor_redhat5.5MEDIUM
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GHSA
pypdf: Possible infinite loop when processing outlines/bookmarks in writer
ghsa·2026-06-16
CVE-2026-54531 [MEDIUM] CWE-835 pypdf: Possible infinite loop when processing outlines/bookmarks in writer
pypdf: Possible infinite loop when processing outlines/bookmarks in writer
### Impact
An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires merging a file with outlines into a writer.
### Patches
This has been fixed in [pypdf==6.13.0](https://github.com/py-pdf/pypdf/releases/tag/6.13.0).
### Workarounds
If you cannot upgrade yet, consider applying the changes from PR [#3830](https://github.com/py-pdf/pypdf/pull/3830).
Red Hat
pypdf: pypdf: Denial of Service via crafted PDF with outlines
vendor_redhat·2026-06-22·CVSS 5.5
CVE-2026-54531 [MEDIUM] CWE-835 pypdf: pypdf: Denial of Service via crafted PDF with outlines
pypdf: pypdf: Denial of Service via crafted PDF with outlines
pypdf is a free and open-source pure-python PDF library. Prior to 6.13.0, an attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires merging a file with outlines into a writer. This vulnerability is fixed in 6.13.0.
A flaw was found in pypdf (before 6.13.0). A crafted PDF with outlines can trigger an infinite loop when merged into a PdfWriter, causing denial of service.
Statement: pypdf is vulnerable to denial of service via infinite loop when merging a crafted PDF with outlines into a PdfWriter. An attacker who can supply such a document for merge processing may hang the application indefinitely. Red Hat exposure mirrors other pypdf consumers: Python services that merge or rewrite
No detection rules found.
No public exploits indexed.
2026-06-22
Published