How severe is CVE-2026-28804?

CVE-2026-28804 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-28804 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-28804?

CVE-2026-28804 affects Pypdf Project Pypdf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-28804?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-28804 have an EU (EUVD) identifier?

Yes. CVE-2026-28804 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10010.

When was CVE-2026-28804 published?

CVE-2026-28804 was published on 2026-03-06 and last updated on 2026-06-17.

CVE-2026-28804

CVE-2026-28804 is a medium-severity vulnerability in Pypdf Project Pypdf with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-407.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v4: 6.9
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-10010
Weakness: CWE-407
Affected product: Pypdf Project Pypdf
Published: 2026-03-06
Last modified: 2026-06-17

Description

pypdf is a free and open-source pure-python PDF library. Prior to version 6.7.5, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /ASCIIHexDecode filter. This issue has been patched in version 6.7.5.

Frequently asked questions

What is CVE-2026-28804?: pypdf is a free and open-source pure-python PDF library. Prior to version 6.7.5, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /ASCIIHexDecode filter. This issue has been patched in version 6.7.5.
How severe is CVE-2026-28804?: CVE-2026-28804 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-28804 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-28804?: CVE-2026-28804 affects Pypdf Project Pypdf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-28804?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-28804 have an EU (EUVD) identifier?: Yes. CVE-2026-28804 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-10010.
When was CVE-2026-28804 published?: CVE-2026-28804 was published on 2026-03-06 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:pypdf_project:pypdf:*:*:*:*:*:*:*:*

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