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Fencer Intel
medium 5.0

CVE-2021-40336 json

HTTP Response Splitting in Hitachi Energy’s MSM Product

published 4y ago modified 4mo ago also EUVD-2021-27515

cvss
5.0
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 43%
public exploits
0
none known

Summary

A vulnerability exists in the http web interface where the web interface does not validate data in an HTTP header. This causes a possible HTTP response splitting, which if exploited could lead an attacker to channel down harmful code into the user’s web browser, such as to steal the session cookies. Thus, an attacker who successfully makes an MSM user who has already established a session to MSM web interface clicks a forged link to the MSM web interface, e.g., the link is sent per E-Mail, could trick the user into downloading malicious software onto his computer. This issue affects: Hitachi Energy MSM V2.2 and prior versions.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

cisa ICSA-22-277-02 updated cvss 5.0

Hitachi Energy Modular Switchgear Monitoring (MSM)

  • Hitachi Energy MSM <= 2.2
    affected: vendor fix, mitigation “Hitachi Energy recommends security practices and firewall configurations to help protect a network from attacks originating outside the network” search.abb.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

Exploit prediction

0.50% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 5.0 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L
NVD 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products

  • Hitachi Energy MSM

Classification

Weakness
  • CWE-113 Improper Neutralization of CRLF Sequences in HTTP Headers
  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.