CVE-2026-27810

MEDIUMNVD 6.46.4
EchelonGraph scoreLOW confidence

This medium-severity CVE scores 6.4 under NVD CVSS v3. EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). 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: nvd
Trending — 3 sources updated this week
6.4EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.4Exploit: None knownExposed: 0

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

calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books. Prior to version 9.4.0, an HTTP Response Header Injection vulnerability in the calibre Content Server allows any authenticated user to inject arbitrary HTTP headers into server responses via an unsanitized content_disposition query parameter in the /get/ and /data-files/get/ endpoints. All users running the calibre Content Server with authentication enabled are affected. The vulnerability is exploitable by any authenticated user and can also be triggered by tricking an authenticated victim into clicking a crafted link. Version 9.4.0 contains a fix for the issue.

CVSS v3
6.4
EG Score
6.4(low)
EG Risk
33(Track)
EG Risk 33/100SSVC: Track

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
Severity64% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
11%
KEV
Not listed

Published

February 27, 2026

Last Modified

June 17, 2026

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 6× in last 7d / 6× 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. 2026-08-01 04:16 UTCEPSS rescore
  2. 2026-07-30 16:27 UTCEPSS rescore
  3. 2026-07-30 01:30 UTCEPSS rescore
  4. 2026-07-28 15:36 UTCEPSS rescore
  5. 2026-07-27 14:03 UTCEG score recompute
  6. 2026-07-27 13:55 UTCOSV refresh

Frequently asked(5)

What is CVE-2026-27810?
CVE-2026-27810 is a medium vulnerability published on February 27, 2026. calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books. Prior to version 9.4.0, an HTTP Response Header Injection vulnerability in the calibre Content Server allows any authenticated user to inject arbitrary HTTP headers into server responses via an…
When was CVE-2026-27810 disclosed?
CVE-2026-27810 was first published in the National Vulnerability Database on February 27, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-27810 actively exploited?
CVE-2026-27810 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 89.1% of all scored CVEs.
What is the CVSS score of CVE-2026-27810?
CVE-2026-27810 has a CVSS v3 base score of 6.4 (NVD). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-27810?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-27810, 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

Explore the affected products and dependency analysis for CVE-2026-27810

Explore →

Is Your Infrastructure Affected by CVE-2026-27810?

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