Security readout for executives and security teams
Plain-English summary
CVE-2026-22036 can let a malicious HTTP server force a Node.js application using Undici/Fetch to spend excessive CPU and memory processing response compression headers. The impact is service slowdown or outage, not data theft. It matters most where applications fetch content from untrusted or attacker-influenced URLs.
Executive priority
Treat as a moderate availability risk. Patch during the next regular security update cycle, faster for systems that fetch untrusted internet URLs or run customer-facing workflows where CPU or memory exhaustion could cause outages.
Technical view
Undici before fixed releases allows an unbounded decompression chain from HTTP Content-Encoding response headers. With the default maxHeaderSize, a malicious server can define many compression steps, causing resource exhaustion. CVSS is 5.9, AV:N/AC:H/PR:N/UI:N, with availability impact only. It is classified as CWE-770.
Likely exposure
Exposure is most likely in Node.js services that use Undici or the Fetch API to make outbound HTTP requests to untrusted, user-supplied, or third-party endpoints. Internal-only clients calling trusted services are less exposed but still should update dependencies.
Exploitation context
The sources do not report active exploitation, and this CVE is not marked as CISA KEV in the provided bundle. Exploitation requires a malicious or controlled HTTP server response and is rated high attack complexity, but no credentials or user interaction are required.
Researcher notes
The provided data conflicts on the 7.x fixed boundary: the description says 7.18.0, while affected versions indicate <7.18.2. Do not assume a specific 7.x safe version without checking the vendor advisory. No confidentiality or integrity impact is identified in the CVSS vector.
Mitigation direction
- Upgrade Undici to a non-vulnerable release per the GitHub advisory.
- Prioritize at least 6.23.0 for 6.x deployments where applicable.
- For 7.x, verify the exact fixed version with vendor guidance due source version inconsistency.
- Avoid fetching arbitrary user-supplied URLs until upgraded.
- Monitor outbound HTTP clients for unusual CPU or memory spikes.
Validation and detection
- Inventory Node.js applications using Undici directly or through Fetch.
- Check package-lock, pnpm-lock, yarn.lock, or SBOMs for vulnerable Undici versions.
- Confirm deployed containers and serverless bundles include the updated dependency.
- Review code paths that fetch user-controlled or third-party URLs.
- Validate remediation against the GitHub advisory and commit reference.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-770: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2026-22036 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 5.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H2.23.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.9MediumVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/nodejs/undici/security/advisories/GHSA-g9mf-h72j-4rw9CVE reference · x_refsource_CONFIRM
- https://github.com/nodejs/undici/commit/b04e3cbb569c1596f86c108e9b52c79d8475dcb3CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Allocation of Resources Without Limits or Throttling
Allocation of Resources Without Limits or Throttling represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.