CVE-2026-82520
CVE-2026-82520
parsedmarc before 11.0.1 decompresses gzip and ZIP attachments in a single unbounded read with no limit on decompressed output size. Because parsedmarc automatically processes incoming DMARC report emails without user interaction, an unauthenticated remote attacker can send a crafted email with a highly compressed attachment to the monitored mailbox, causing the parsedmarc process to allocate memory proportional to the uncompressed size and exhaust available RAM.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
EPSS: 0.008 (55.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 55.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.008 · change: +0.003
Weakness classification (CWE)
References
- github.com/domainaware/parsedmarc/releases/tag/11.0.1 (release-notes, patch)
- github.com/domainaware/parsedmarc/security/advisories/GHSA-43qf-f35w-2x4r (vendor-advisory)
- www.vulncheck.com/advisories/parsedmarc-zip-bomb-dos-via-compressed-email-attac… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-82520?
- CVE-2026-82520 is a high-severity vulnerability, classified under Improper Handling of Highly Compressed Data (Data Amplification). CVSS score: 7.5/10. Published 2026-09-03.
- How severe is CVE-2026-82520?
- High severity. CVSS v3 base score is 7.5 out of 10.