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Not in CISA KEV

GHSA-x7hp-r3qg-r3cj — pypdf

Fix: py-pdf/pypdf#3658

GHSA-x7hp-r3qg-r3cj is a Uncontrolled Resource Consumption vulnerability in pypdf. A fix is available for pypdf — see the affected versions and patch details below.

pypdf: Manipulated FlateDecode XFA streams can exhaust RAM

Also known asCVE-2026-27888PYSEC-2026-3027
Published
Feb 26, 2026
Updated
Jul 13, 2026
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed
Exploitation data as of Sep 26, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

  • CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
  • CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-x7hp-r3qg-r3cj.

EPSS Exploitation Probability

via FIRST.org ↗
0.6%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs49th percentile — riskier than 49% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

1 pkg affected
🐍pypdf

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

Impact

An attacker who uses this vulnerability can craft a PDF which leads to the RAM being exhausted. This requires accessing the xfa property of a reader or writer and the corresponding stream being compressed using /FlateDecode.

Patches

This has been fixed in pypdf==6.7.3.

Workarounds

If projects cannot upgrade yet, consider applying the changes from PR #3658.

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
🐍PyPIpypdfall versions6.7.3pip install --upgrade 'pypdf==6.7.3'

Detection & mitigation playbook

Open-source dependency
  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pypdf, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update pypdf to 6.7.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-x7hp-r3qg-r3cj is resolved across your whole dependency graph.

  3. Workarounds

    If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

  4. How O3 protects you

    O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-x7hp-r3qg-r3cj can be triaged on real exposure rather than presence alone.

Tailored to GHSA-x7hp-r3qg-r3cj. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate
ProductFixed inAdvisory
Red Hat OpenShift AI 2.25rhoai/odh-llama-stack-core-rhel9:1775144403RHSA-2026:10184

Frequently Asked Questions

### Impact An attacker who uses this vulnerability can craft a PDF which leads to the RAM being exhausted. This requires accessing the `xfa` property of a reader or writer and the corresponding stream being compressed using `/FlateDecode`. ### Patches This has been fixed in [pypdf==6.7.3](https://github.com/py-pdf/pypdf/releases/tag/6.7.3). ### Workarounds If projects cannot upgrade yet, consider applying the changes from PR [#3658](https://github.com/py-pdf/pypdf/pull/3658).
O3 Security · Impact-Aware SCA

Is GHSA-x7hp-r3qg-r3cj in your dependencies?

O3 Security finds GHSA-x7hp-r3qg-r3cj across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

GHSA-x7hp-r3qg-r3cj: pypdf | O3 Security