CVE-2026-33206Public exploit

Local file disclosure via unnormalized image paths

Published Mar 27, 2026 · Updated Mar 27, 2026

Path traversal in calibre before 9.6.0 allows attackers to read arbitrary local files by supplying a crafted text-based e-book. The txt_input.py fix_resources routine joins an image src to base_dir but checks the unnormalized path prefix, so ../ segments escape the intended directory. Exploitation requires a user to open or convert the file; a linked unauthenticated reader endpoint can then exfiltrate included data without further interaction.

CVSS severity8.2
High
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in calibre before 9.6.0 allows attackers to read arbitrary local files by supplying a crafted text-based e-book. The txt_input.py fix_resources routine joins an image src to base_dir but checks the unnormalized path prefix, so ../ segments escape the intended directory. Exploitation requires a user to open or convert the file; a linked unauthenticated reader endpoint can then exfiltrate included data without further interaction.

The record

CVE
CVE-2026-33206
Published
Mar 27, 2026
Updated
Mar 27, 2026
Vendor
Kovid Goyal
Product
calibre
Classifications
CWE-23, T1005, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 9.6.0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Kovid Goyal · calibreversion=< 9.6.0

Published CVSS scores

6.3NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N
8.2GitHub, Inc.CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-23Relative Path Traversal
T1005Data from Local System
T1204.002User Execution: Malicious File

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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