CVE-2026-15157
undici vulnerable to CRLF Injection via blob-like body 'type' property
Description
undici does not validate the type property of a duck-typed blob-like request body before using it as the Content-Type header on the HTTP/1.1 dispatcher. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, an application that passes a hand-rolled blob-like body (via request, stream, pipeline, or dispatch) whose type is derived from untrusted input allows an attacker to inject CRLF sequences and append arbitrary HTTP headers, potentially smuggling a second request past the upstream. Native Blob objects are safe because their constructor strips CRLF from the type, and fetch is unaffected because it validates headers, but ecosystem libraries that build duck-typed blob shapes from user input can reach the vulnerable path. This is the same defect class as CVE-2022-35948 and CVE-2026-1527, on a header sink that the earlier fixes did not cover. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0.
INFO
Published Date :
July 29, 2026, 10:16 p.m.
Last Modified :
July 29, 2026, 10:16 p.m.
Remotely Exploit :
Yes !
Source :
ce714d77-add3-4f53-aff5-83d477b104bb
Affected Products
The following products are affected by CVE-2026-15157
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | ce714d77-add3-4f53-aff5-83d477b104bb | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE |
Solution
- Update undici to version 6.28.0 or later.
- Update undici to version 7.29.0 or later.
- Update undici to version 8.9.0 or later.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-15157.
| URL | Resource |
|---|---|
| https://cna.openjsf.org/security-advisories.html | |
| https://github.com/nodejs/undici/security/advisories/GHSA-m8rv-5g2x-5cg5 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-15157 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-15157
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-15157 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-15157 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by ce714d77-add3-4f53-aff5-83d477b104bb
Jul. 29, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'undici', 'product': 'undici', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '6.28.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.28.0', 'versionType': 'semver'}, {'status': 'affected', 'version': '7.0.0', 'lessThan': '7.29.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '7.29.0', 'versionType': 'semver'}, {'status': 'affected', 'version': '8.0.0', 'lessThan': '8.9.0', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '8.9.0', 'versionType': 'semver'}], 'packageURL': 'pkg:npm/undici', 'defaultStatus': 'unaffected'}] Added Description undici does not validate the type property of a duck-typed blob-like request body before using it as the Content-Type header on the HTTP/1.1 dispatcher. In undici before 6.28.0, from 7.0.0 up to before 7.29.0, and from 8.0.0 up to before 8.9.0, an application that passes a hand-rolled blob-like body (via request, stream, pipeline, or dispatch) whose type is derived from untrusted input allows an attacker to inject CRLF sequences and append arbitrary HTTP headers, potentially smuggling a second request past the upstream. Native Blob objects are safe because their constructor strips CRLF from the type, and fetch is unaffected because it validates headers, but ecosystem libraries that build duck-typed blob shapes from user input can reach the vulnerable path. This is the same defect class as CVE-2022-35948 and CVE-2026-1527, on a header sink that the earlier fixes did not cover. The issue is fixed in undici 6.28.0, 7.29.0, and 8.9.0. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N Added CWE CWE-93 Added Reference https://cna.openjsf.org/security-advisories.html Added Reference https://github.com/nodejs/undici/security/advisories/GHSA-m8rv-5g2x-5cg5