CVE-2026-33205: calibre-ebook calibre Server-Side Request Forgery (SSRF)
Vulnerability summary
CVE-2026-33205 is a medium (CVSS 5.5) Server-Side Request Forgery (SSRF) vulnerability in calibre-ebook calibre. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 6.2% of scored vulnerabilities. 1 public exploit is recorded.
Advisory lineage
Upstream 0 · Downstream 1 · Related 1Timeline
- 27-03-2026PublishedVulnerability first disclosed.
- 27-03-2026Last modifiedVulnerability information updated.
Description
calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books. Prior to version 9.6.0, a Server-Side Request Forgery vulnerability in the background-image endpoint of calibre e-book reader's web view allows an attacker to perform blind GET requests to arbitrary URLs and exfiltrate information out from the ebook sandbox. Version 9.6.0 patches the issue.
CVSS metrics
6 scores · 4 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated4.8MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
- NVDNIST4.8MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS trend
Probability
0.17%
Chance of exploitation in the next 30 days
Percentile
6%
Versus all other CVEs
30-day change
0.00 pp
From 0.17% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundCalibre
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Calibre-ebook1 product
- calibre< 9.6.0
Debian1 product
- calibre< 6.13.0+repack-2+deb12u9 | < 8.5.0+ds-1+deb13u3 | < 9.6.0+ds+~0.10.5-1
Kovidgoyal1 product
- calibre< 9.6.0
Ubuntu1 product
- calibreAll versions (No fix recorded)
4 vendors · 4 products
References
4 links- github.com/kovidgoyal/calibre/security/advisories/GHSA-4926-v9px-wv7vX Refsource CONFIRMREPORTExploitVendor Advisory
