CyberSecBulletin
CVE-2024-23452NVD status: Modified

Apache bRPC: Inconsistent Interpretation of HTTP Requests

CVE-2024-23452 is a high-severity inconsistent interpretation of HTTP requests vulnerability in Apache bRPC from Apache, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 1.8.0 as the first without the flaw, so updating Apache bRPC to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.64% chance of exploitation within 30 days, higher than 77% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Apache bRPC to 1.8.0 or a later version.
  2. Update Brpc to 1.8.0 or a later version.
  3. Read the advisory on lists.apache.org for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ApacheApache bRPC0.9.5 up to, but not including, 1.8.01.8.0
ApacheBrpc0.9.5 up to, but not including, 1.8.01.8.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
HighData or code can be modified at will.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighNVD
CVSS 3.17.5HighCISA (ADP)

Official description

Request smuggling vulnerability in HTTP server in Apache bRPC 0.9.5~1.7.0 on all platforms allows attacker to smuggle request. Vulnerability Cause Description: The http_parser does not comply with the RFC-7230 HTTP 1.1 specification. Attack scenario: If a message is received with both a Transfer-Encoding and a Content-Length header field, such a message might indicate an attempt to perform request smuggling or response splitting. One particular attack scenario is that a bRPC made http server on the backend receiving requests in one persistent connection from frontend server that uses TE to parse request with the logic that 'chunk' is contained in the TE field. in that case an attacker can smuggle a request into the connection to the backend server. Solution: You can choose one solution from below: 1. Upgrade bRPC to version 1.8.0, which fixes this issue. Download link: https://github.com/apache/brpc/releases/tag/1.8.0 2. Apply this patch: https://github.com/apache/brpc/pull/2518

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Inconsistent Interpretation of HTTP Requests

The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

How developers prevent this class of flaw

  • Use a web server that employs a strict HTTP parsing procedure, such as Apache.
  • Terminate the client session after each request.

More Inconsistent Interpretation of HTTP Requests vulnerabilities (CWE-444)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Apache bRPC

All Apache bRPC vulnerabilities

Recent Inconsistent Interpretation of HTTP Requests vulnerabilities

Spotted an error? Tell us.