Vulnerability · Published Jun 22, 2026 · Assigned by GitHub_M
CVE-2026-49460pypdf: Inefficient decoding of FlateDecode PNG predictor streams
Medium 5.1
In plain English
A medium-severity security flaw in pypdf from py-pdf. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 4.0)5.1Medium
Exploit odds (30 days)0.2%top 94.1% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
pypdf is a free and open-source pure-python PDF library. Prior to 6.12.2, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /FlateDecode filter with a PNG predictor. This vulnerability is fixed in 6.12.2.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | pypdf | no fix listed | DEBIAN-CVE-2026-49460 |
| Debian:13 | pypdf | no fix listed | DEBIAN-CVE-2026-49460 |
| Debian:14 | pypdf | 6.19.0-1 | DEBIAN-CVE-2026-49460 |
| Debian:12 | pypdf2 | no fix listed | DEBIAN-CVE-2026-49460 |
| PyPI | pypdf | 6.12.2 | GHSA-5hgr-hg42-57jg |
| PyPI | pypdf | 6.12.2 | PYSEC-2026-3010 |
| Ubuntu:24.04:LTS | pypdf | no fix listed | UBUNTU-CVE-2026-49460 |
| Ubuntu:25.10 | pypdf | no fix listed | UBUNTU-CVE-2026-49460 |
| Ubuntu:26.04:LTS | pypdf | no fix listed | UBUNTU-CVE-2026-49460 |
| Ubuntu:26.10 | pypdf | no fix listed | UBUNTU-CVE-2026-49460 |
| Ubuntu:22.04:LTS | pypdf2 | no fix listed | UBUNTU-CVE-2026-49460 |
| Ubuntu:24.04:LTS | pypdf2 | no fix listed | UBUNTU-CVE-2026-49460 |
Affected products (as reported)
Weakness: CWE-407 · Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
References
- https://github.com/py-pdf/pypdf/security/advisories/GHSA-5hgr-hg42-57jg x_refsource_CONFIRM
- https://github.com/py-pdf/pypdf/pull/3806 x_refsource_MISC
- https://github.com/py-pdf/pypdf/releases/tag/6.12.2 x_refsource_MISC