CVE-2026-71870
published 2026-08-07CVE-2026-71870: pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause large memory consumption when pypdf/_cmap.py function…
PriorityP411low3.3CVSS 3.1
AVLACLPRNUIRSUCNINAL
EPSS
0.13%
2.0th percentile
pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause large memory consumption when pypdf/_cmap.py function parse_bfrange parses unusually large source-code or destination-string tokens in a font /ToUnicode CMap during text extraction. This issue is fixed in 6.15.0.
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| py-pdf | pypdf | < 6.15.0 | 6.15.0 |
| pypdf_project | pypdf | < 6.15.0 | 6.15.0 |
| pypdf_project | pypdf | >= 0 < 6.15.0 | 6.15.0 |
CVSS provenance
nvdv3.13.3LOWCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
nvdv4.04.8MEDIUMCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/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_redhat4.8MEDIUM
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GHSA
pypdf: Possible large memory usage for large /ToUnicode streams
ghsa·2026-08-07
CVE-2026-71870 [MEDIUM] CWE-400 pypdf: Possible large memory usage for large /ToUnicode streams
pypdf: Possible large memory usage for large /ToUnicode streams
### Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory consumption. This requires parsing the `/ToUnicode` entry of a font with unusually large values, for example during text extraction.
### Patches
This has been fixed in [pypdf==6.15.0](https://github.com/py-pdf/pypdf/releases/tag/6.15.0).
### Workarounds
If you cannot upgrade yet, consider applying the changes from PR [#3944](https://github.com/py-pdf/pypdf/pull/3944).
VulDB
py-pdf pypdf up to 6.14.x CMap Parsing pypdf/_cmap.py parse_bfrange memory allocation
vuldb·2026-08-07·CVSS 4.8
CVE-2026-71870 [MEDIUM] py-pdf pypdf up to 6.14.x CMap Parsing pypdf/_cmap.py parse_bfrange memory allocation
A vulnerability marked as problematic has been reported in py-pdf pypdf up to 6.14.x. This issue affects the function parse_bfrange of the file pypdf/_cmap.py of the component CMap Parsing. The manipulation leads to uncontrolled memory allocation.
This vulnerability is listed as CVE-2026-71870. The attack may be initiated remotely. There is no available exploit.
It is suggested to upgrade the affected component.
Red Hat
pypdf: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams
vendor_redhat·2026-08-07·CVSS 4.8
CVE-2026-71870 [MEDIUM] CWE-770 pypdf: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams
pypdf: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams
A flaw was found in pypdf, a pure-python PDF library. A remote attacker could exploit this vulnerability by providing a specially crafted PDF file. When the library attempts to parse unusually large font /ToUnicode CMap streams during text extraction, it can lead to excessive memory consumption. This can result in a denial of service (DoS) for applications processing such malicious PDF files.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-71870 python-PyPDF2: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams [fedora-all]
bugzilla·2026-08-09·CVSS 4.8
CVE-2026-71870 [MEDIUM] CVE-2026-71870 python-PyPDF2: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams [fedora-all]
CVE-2026-71870 python-PyPDF2: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause large memory consumption when pypdf/_cmap.py function parse_bfrange parses unusually large source-code or destination-string tokens in a font /ToUnicode CMap during text extraction. This issue is fixed in 6.15.0.
Bugzilla
CVE-2026-71870 python-pypdf: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams [fedora-all]
bugzilla·2026-08-09·CVSS 4.8
CVE-2026-71870 [MEDIUM] CVE-2026-71870 python-pypdf: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams [fedora-all]
CVE-2026-71870 python-pypdf: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause large memory consumption when pypdf/_cmap.py function parse_bfrange parses unusually large source-code or destination-string tokens in a font /ToUnicode CMap during text extraction. This issue is fixed in 6.15.0.
Bugzilla
CVE-2026-71870 pypdf: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams
bugzilla·2026-08-07·CVSS 4.8
CVE-2026-71870 [MEDIUM] CVE-2026-71870 pypdf: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams
CVE-2026-71870 pypdf: pypdf: Denial of Service via crafted PDF with large /ToUnicode streams
pypdf is a free and open-source pure-python PDF library. Prior to 6.15.0, a crafted PDF can cause large memory consumption when pypdf/_cmap.py function parse_bfrange parses unusually large source-code or destination-string tokens in a font /ToUnicode CMap during text extraction. This issue is fixed in 6.15.0.
2026-08-07
Published