CVE-2023-0040

HIGH
7.5
CVSS Score
Published: January 18, 2023 at 12:00 AM UTC
Updated: June 17, 2026 at 05:24 AM UTC
1 product affected across 1 vendorAsyncHttpClient

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Severity
HIGH7.5
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

Description

Versions of Async HTTP Client prior to 1.13.2 are vulnerable to a form of targeted request manipulation called CRLF injection. This vulnerability was the result of insufficient validation of HTTP header field values before sending them to the network. Users are vulnerable if they pass untrusted data into HTTP header field values without prior sanitisation. Common use-cases here might be to place usernames from a database into HTTP header fields. This vulnerability allows attackers to inject new HTTP header fields, or entirely new requests, into the data stream. This can cause requests to be understood very differently by the remote server than was intended. In general, this is unlikely to result in data disclosure, but it can result in a number of logical errors and other misbehaviours.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 1.13.1v < 1.4.11.10.0 ≤ v < 1.12.11.13.0 ≤ v < 1.13.21.5.0 ≤ v < 1.9.1
Affected range stops below 1.12.1, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.13.2, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.4.1, so it looks safe — our inference, not a vendor statement
Affected range stops below 1.9.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHCISA-ADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-93CWE-74

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