CVE-2026-33805

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.44% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 36.6% of scored records. A rank, not a probability.

NVD base score

9.0 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:L/SI:H/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

NVD analysis status

Modified. NVD last modified this record on 2026-07-15.

Red Hat severity

Important. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-04-15 10:13Z4 MO AGO

Last updated

2026-07-15 01:06Z1 MO AGO

Reserved

2026-03-23

Assigning CNA

openjs

Record state

PUBLISHED

Severity

Critical (CVSS 9.0)

CNA CVSS vector

CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:L/SI:H/SA:N

Weaknesses

• CWE-644Improper Neutralization of HTTP Headers for Scripting SyntaxVariant
• CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')Base

Data version

5.2

Document digest

294755384317aaaed6c1f664136f875f480d572d7d6952286b314f21f5a4c8d2

• github.comhttps://github.com/fastify/fastify-reply-from/security/advisories/GHSA-gwhp-pf74-vj37
• cna.openjsf.orghttps://cna.openjsf.org/security-advisories.html
• access.redhat.comhttps://access.redhat.com/security/cve/CVE-2026-33805vdb-entryx_refsource_REDHAT
• bugzilla.redhat.comRHBZ#2458651https://bugzilla.redhat.com/show_bug.cgi?id=2458651issue-trackingx_refsource_REDHAT
• security.access.redhat.comhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33805.jsonx_sadp-csaf-vex
• access.redhat.comhttps://access.redhat.com/errata/RHSA-2026:10175vendor-advisoryx_refsource_REDHAT