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No exploitation reportedFix available

CVE-2021-36978

No exploitation reported by the sources we read.

  • Published2021-07-20
  • WeaknessCWE-787

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

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 from Pl_AES_PDF::flush and Pl_AES_PDF::finish) when a certain downstream write fails.

Timeline

dates in UTC
  1. 2021-07-2007:15CVE publishedNVD

Versions per branch

NVD
Qpdf project qpdf
BranchAffectedFixed in
9.x≥ 9.0.0, ≤ 9.1.1no fix published
10.0≥ 10.0.0, ≤ 10.0.4no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • qpdfUbuntu:Pro:16.04:LTSall versions · fixed in 8.0.2-3~16.04.1+esm1
  • qpdfUbuntu:20.04:LTSall versions · fixed in 9.1.1-1ubuntu0.1
  • qpdfUbuntu:18.04:LTSall versions · fixed in 8.0.2-3ubuntu0.1
  • qpdfSUSE:OpenStack Cloud Crowbar 9all versions · fixed in 7.1.1-3.8.1
  • qpdfSUSE:OpenStack Cloud 9all versions · fixed in 7.1.1-3.8.1
  • qpdfSUSE:Manager Server 4.1all versions · fixed in 9.0.2-150200.3.3.1
  • qpdfSUSE:Manager Retail Branch Server 4.1all versions · fixed in 9.0.2-150200.3.3.1
  • qpdfSUSE:Manager Proxy 4.1all versions · fixed in 9.0.2-150200.3.3.1

33 more package ranges on OSV.dev

Full record on NVD

Fix

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Published
2021-07-20
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-vgrr-57vg-f5rq

Frequently asked questions

What is CVE-2021-36978?

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 from Pl_AES_PDF::flush and Pl_AES_PDF::finish) when a certain downstream write fails.

Is CVE-2021-36978 actively exploited?

Active exploitation of CVE-2021-36978 has not been confirmed. Its EPSS score was 1.3% on 2026-11-08, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-36978?

CVE-2021-36978 has a CVSS v3 base score of 5.5 (MEDIUM severity), with vector string CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.

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Sources for this record