CVE-2026-55195

HIGHPre-NVD 8.78.7—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2%, top 89% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Elevated
8.7EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.7Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

py7zr is a Python-based library and utility to support 7zip archive compression, decompression, encryption and decryption. Prior to 1.1.3, py7zr's Worker.decompress() extracted archive entries without tracking total decompressed size, allowing a crafted .7z file such as a 15.6 KB archive that expands to 100 MB to exhaust disk or memory before extraction completes. This issue is fixed in version 1.1.3.

CVSS v3
8.7
EG Score
8.7(medium)
EG Risk
70(Attend)
EG Risk 70/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity87% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
11%
KEV
Not listed

Published

June 19, 2026

Last Modified

July 10, 2026

Advisory Details (3)

Auto-updated Jul 8, 2026
🔬 Proof of concept available. Patch available. Sources: github, github_commit, github_release.
github_release Patch Available

Release version 1.1.3: Fix multiple vulnerabilities

Patch available: miurahr/py7zr v1.1.3

https://github.com/miurahr/py7zr/releases/tag/v1.1.3
github_commit Patch Available

commit 28faf107b643 (miurahr/py7zr)

Patch available: miurahr/py7zr v1.1.3 (contains commit 28faf107b643)

https://github.com/miurahr/py7zr/commit/28faf107b64374fa5a02bfb93aa2024e281ca97b
github Patch Available🟡 PoC Available

py7zr <= 1.1.2: Decompression bomb (zip bomb) denial of service via unchecked extraction size · Advisory · miurahr/py7zr · GitHub

https://github.com/miurahr/py7zr/security/advisories/GHSA-gjrg-mpp7-g774

Vendor Advisories for CVE-2026-55195(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(1 across 1 ecosystem)
PyPI(1)
PackageVulnerable rangeFixed inDependents
py7zr0.0.3 ... 1.1.2 (164 versions)1.1.3—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 9× in last 7d / 28× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-26 16:47 UTCEG score recompute
  2. 2026-07-26 14:54 UTCEPSS rescore
  3. 2026-07-25 14:18 UTCEPSS rescore
  4. 2026-07-24 14:18 UTCEPSS rescore
  5. 2026-07-23 14:18 UTCEPSS rescore
  6. 2026-07-23 03:20 UTCEG score recompute
  7. 2026-07-22 14:08 UTCEPSS rescore
  8. 2026-07-21 15:25 UTCEPSS rescore
  9. 2026-07-20 17:08 UTCEPSS rescore
  10. 2026-07-19 14:31 UTCEPSS rescore
  11. 2026-07-19 14:31 UTCEPSS rescore
  12. 2026-07-19 02:29 UTCEPSS rescore
  13. 2026-07-18 10:04 UTCEPSS rescore
  14. 2026-07-16 17:03 UTCEPSS rescore
  15. 2026-07-15 16:57 UTCEPSS rescore
  16. 2026-07-15 16:57 UTCEPSS rescore
  17. 2026-07-15 02:00 UTCEPSS rescore
  18. 2026-07-15 02:00 UTCEPSS rescore
  19. 2026-07-13 22:31 UTCEPSS rescore
  20. 2026-07-13 06:13 UTCEPSS rescore
  21. 2026-07-13 06:13 UTCEPSS rescore
  22. 2026-07-12 05:46 UTCEPSS rescore
  23. 2026-07-11 08:27 UTCEPSS rescore
  24. 2026-07-11 08:27 UTCEPSS rescore
  25. 2026-07-09 19:10 UTCEPSS rescore
Show 4 more
  1. 2026-07-09 19:10 UTCEPSS rescore
  2. 2026-07-08 20:45 UTCEG score recompute▲ 8.70
  3. 2026-07-08 20:44 UTCMITRE cvelistV5CVSS v3 → 8.7 · CVSS v4 → 8.7 · severity → HIGH
  4. 2026-06-19 21:23 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-55195?
CVE-2026-55195 is a high vulnerability published on June 19, 2026. py7zr is a Python-based library and utility to support 7zip archive compression, decompression, encryption and decryption. Prior to 1.1.3, py7zr's Worker.decompress() extracted archive entries without tracking total decompressed size, allowing a crafted .7z file such as a 15.6 KB archive that…
When was CVE-2026-55195 disclosed?
CVE-2026-55195 was first published in the National Vulnerability Database on June 19, 2026, with the most recent update on July 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55195 actively exploited?
CVE-2026-55195 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 88.7% of all scored CVEs.
What is the CVSS score of CVE-2026-55195?
CVE-2026-55195 has a CVSS v3 base score of 8.7 (NVD).
How do I remediate CVE-2026-55195?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55195, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-55195

Explore →

Is Your Infrastructure Affected by CVE-2026-55195?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs