How severe is CVE-2021-25786?

CVE-2021-25786 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2021-25786 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (39th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-25786?

CVE-2021-25786 affects Qpdf Project Qpdf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-25786?

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

When was CVE-2021-25786 published?

CVE-2021-25786 was published on 2023-08-11 and last updated on 2026-06-17.

CVE-2021-25786

CVE-2021-25786 is a medium-severity vulnerability in Qpdf Project Qpdf 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-416.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 1% (39th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Qpdf Project Qpdf
Published: 2023-08-11
Last modified: 2026-06-17

Description

An issue was discovered in QPDF version 10.0.4, allows remote attackers to execute arbitrary code via crafted .pdf file to Pl_ASCII85Decoder::write parameter in libqpdf.

Frequently asked questions

What is CVE-2021-25786?: An issue was discovered in QPDF version 10.0.4, allows remote attackers to execute arbitrary code via crafted .pdf file to Pl_ASCII85Decoder::write parameter in libqpdf.
How severe is CVE-2021-25786?: CVE-2021-25786 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2021-25786 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (39th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-25786?: CVE-2021-25786 affects Qpdf Project Qpdf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-25786?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-25786 published?: CVE-2021-25786 was published on 2023-08-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:qpdf_project:qpdf:10.0.4:*:*:*:*:*:*:*

More vulnerabilities in Qpdf Project Qpdf

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CVE-2024-24246 — Medium (CVSS 5.5): Heap Buffer Overflow vulnerability in qpdf 11.9.0 allows attackers to crash the application via the…
CVE-2021-36978 — Medium (CVSS 5.5): QPDF 9.x through 9.1.1 and 10.x through 10.0.4 has a heap-based buffer overflow in Pl_ASCII85Decoder::write (called…
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Other CWE-416 (Use After Free) vulnerabilities

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CVE-2026-4688 — Critical (CVSS 10.0): Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox…
CVE-2025-24085 — Critical (CVSS 10.0): A use after free issue was addressed with improved memory management. This issue is fixed in iOS 18.3 and iPadOS 18.3,…
CVE-2024-43102 — Critical (CVSS 10.0): Concurrent removals of certain anonymous shared memory mappings by using the UMTX_SHM_DESTROY sub-request of…
CVE-2021-32495 — Critical (CVSS 10.0): Radare2 has a use-after-free vulnerability in pyc parser's get_none_object function. Attacker can read freed memory…

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